
Gass I A^"] ^ 
Book o y /? ^ 



Issued February 10, 1912. 

U. S. DEPARTMENT OE AGRICULTURE. 

BUREAU OF CHEMISTRY— BULLETIN No. 147. 

H. W. WILKY, Chief of Bureau. 



COAL-TAR COLORS USED IN 
FOOD PRODUCTS. 



BERNHARD C. HESSE, Ph. D. 

Expert, Bureau Chemistry. 




WASHINGTON: 
GOVERNMENT PRINTING OFFICE. 

1912. , 



Issued February 10, 1912. 

y. S. DEPARTMENT OF AGRICULTURE, 

BUREAU OF CHEMISTRY— BULLETIN ho. i47. 

H. W. WILEY, Chief of Bureau. 



COAL-TAE COLORS USED IN 



FOOD PRODUCTS. 



.1 



BY 



BERNHARD C. HESSE, Ph. D. 

Expert, Bureau Chemistry. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 

1912. 



ORGANIZATION OF BUREAU OF CHEMISTRY. ^ "^ V 

H. W. Wiley, Chemist and Chief of Bureau. n ^ 

F. L. DuNLAP, Associate Chemist, and Acting Chief in absence of Chief. ^ 
W. D. BiGELOw, Assistant Chief of Bureau. ^ 

F. B. Linton, Chief Clerk. 
A. L, Pierce, Editor. 
A. E. Draper, Librarian. 

Division of Foods, W. D. Bigelow, Chief. 

Food-Inspection Laboratory, L. M. Tolman, Chief. 

Food Technology Laboratory, E. M. Chace, Chief and Assistant Chief of Division. 

Oil, Fat, and Wax Laboratory, H. S. Bailey, Chief. 
Division of Drugs, L. F, Kebler, Chief. 

Drug-Inspection Laboratory, G. W. Hoover, Chief. 

Synthetic Products Laboratory, W. 0. Emery, Chief. 

Essential Oils Laboratory, under Chief of Division. 

Pharmacological Laboratory, Wm. Salant, Chief. 
Cliief Food and Drug Inspector, W^. G. Campbell. 
Miscellaneous Division, J. K. Haywood, Chief 

Water Laboratory, W. W. Skinner, Chief. 

Cattle-Fbod and Grain Laboratory, G, L. Bidwell, Acting. 

Insecticide and Fungicide Laboratory, C. C. McDonnell, Chief. 

Trade Wastes Laboratory, under Chief of Division. 
Contracts Laboratory, P. H. Walker, Chief. 
Dairy Laboratory, G. E. Patrick, Chief. 
Food Research. Laboratory, M. E. Pennington, Chief. 
Leather and Paper Laboratory, F. P. Veitch, Chief 
Microchemical Laboratory, B. J. Howard, Chief. 
Physical Chemistry Laboratory, C. S. Hudson, Chief 
Sugar Laboratory, A. H. Bryan, Chief. 
Sections: 

Animal Physiological Chemistry, F. C. Weber, in Charge. 

Bacteriological Chemistry, G. W. Stiles, in Charge. 

Enological Chemistry, W. B. Alwood, in Charge. 

Nitrogen, T. C. Trescot, in Charge. 

Plant Physiological Chemistry, J. A. Le Clerc, Chief 
Food and Drug Inspection Laboratories: 

Boston, B. H. Smith, Chief. 

Buffalo, W. L. Dubois, Chief. 

Chicago, A. L. Winton, Chief. 

Cincinnati, B. R. Hart, Chief 

Denver, R. S. Hiltner, Chief. 

Detroit, H. L. Schulz, Chief. 

Galveston, T. F. Pappe, Chief. 

Honolulu, Hawaii, 

Kansas City, Mo., F. W. Liepsner, Chief. 

Nashville, R. W. Balcom, Chief. 

New Orleans, W. J. McGee, Chief. 

New York, R. E. Doolittle, Chief. 

Omaha, S. H. Ross, Chief. 

Philadelphia, C. S. Brinton, Chief. 

Pittsburg, M. C. Albrech, Chief. _ ^• 

Portland, Oreg., A. L. Knisely, Chief.' 

St. Louis, D. B. Bisbee, CAi€/. 

St. Paul, A. S. Mitchell, Chief. 

San Francisco, R. A. Gould, Chief 

San Juan, Porto Rico, A. E. Taylor, Acting. 

Savannah, W. C. Burnet, Chief. 

Seattle, H. M. Loomis, Chief. 

2 .v; 



LETTER OF TRANSMITTAL 



U. S. Department of Agriculture, 

Bureau of Chemistry, 
Washington, D. C, January 31, 1911. 
Sir: I have the honor to transmit for your approval a report by 
Bernhard C. Hesse, a color expert, containing both original chemical 
work done in the bureau since the passage of the food law on anilin 
dyes used for foods, and a valuable and extensive compilation of the 
literature of the subject, especially with reference to the harmfulness 
of coal-tar colors and their physiological effects. These data formed 
the basis of the opinions stated in Food Inspection Decisions 76, 77, 
and 106, and are presented in detail as of scientific and practical 
interest to all those concerned in the use of coal-tar colors in foods, 
whether as manufacturers, food officials, or consumers. I recommend 
the publication of this report as Bulletin No. 147 of the Bureau of 
Chemistry. 

Respectfully, H. W. Wiley, Chief, 

Hon. James Wilson, 

Secretary of Agriculture. 



CONTENTS. 



Page. 

Introduction 9 

Purpose of the investigation 9 

Number of colors permitted 11 

Quality and efficiency of colors permitted 12 

I. Identity of coal-tar colors used in food products in the United States 

in 1907 15 

Collection of samples 15 

Classification of samples submitted 17 

Green Table numbers 17 

Source 18 

Patents 18 

Shades of color 19 

n. Purposes of food coloring 23 

in. Food color requirements 25 

Adaptability for special purposes : 25 

Proportion of coal-tar color used 26 

Suitability of shades of permitted colors and mixtures of same 28 

IV. Conformity of food color market, 1907, to recommendations of the 

National Confectioners' Association, 1899 30 

V. Some legal enactments relative to the use of coal-tar dyes 35 

List of thirteen foreign legal enactments 35 

Summary of colors permitted by these legal enactments 35 

Colors said to be permitted under the German law of 1887 37 

Definiteness and detail necessary to effect quality control 40 

State laws prohibiting the use of colors in certain foods, 1909 41 

VI. Recommendations by associations and individuals as to use of coal-tar 

dyes as food colors : 42 

Cazeneuve and Lepine 42 

Society of Swiss Analytical Chemists 43 

Tschirch 43 

Kayser 44 

Weyl 44 

National Confectioners' Association 45 

Schacherl 45 

Classification of recommendations in the literature 46 

Conclusions 47 

Vn. Recommendations made by United States color industries and trades 

to the Department of Agriculture 47 

Antagonistic to all added artificial color 48 

Concerning restrictions and requirements 48 

Vin. Investigations, other than on animals, bearing on the harmfulness of 

coal-tar colors. 51 

Pfeffer 51 

Winogradow 52 

Heidenhain 52 

Other authors 54 

5 



6 COlSnCENTS. 

Page. 

IX. Compilation under the Green Table numbers of all information avail- 

able as to the suitability of coal-tar colors for food 56 

General statements 56 

Classification of opinions in literature and in legal enactments showing 

condition of the market in 1907 62 

Classification according to chemical composition and suitability 64 

Physiological action of coal-tar dyes 67 

Summary of symptoms 67 

Experiments on dogs 67 

Experiments on human beings 70 

Experiments on small animals 71 

General statements 71 

Complete detailed statement of all combined data 74 

Abbreviations of authorities cited 74 

Tabulation by Green Table numbers of physiological and other data 75 

Alphabetical index of trade names of coal-tar colors. 148 

X. Dosage and symptoms 153 

Confectioner's list as a basis for a rule 153 

Lehmann's rules 158 

Santori's work as a guide to a rule 158 

Young's rule 159 

XI. Oil-soluble or fat colors 159 

Xn. Rules and reasons for selecting the seven colors permitted by F. I. D. 76. . 161 

Statement of rules 161 

Analysis of three recommendations made to the Department of Agri- 
culture 162 

Process of elimination 166 

Reasons for adding Ponceau 311 167 

Quality, cleanliness, and efiiciency 169 

Xm. Lists of colors subsequently recommended by individuals and asso- 
ciations 169 

Ernst 170 

Muttelet's interpretation of the French law 171 

Second International White Cross Congress 172 

Beythien and Hempel 173 

Summary of three preceding recommendations 174 

Unpublished recommendations of a manufacturer 177 

B^hal 177 

Conclusions 178 

XIV Chemical examination of the seven permitted colors, 1907 179 

Need of chemical control 179 

First methods of analysis used 181 

Moisture . 182 

Chlorin as chlorids 182 

Sulphated ash 182 

Total sulphur 183 

Gutzeit test 183 

Heavy metals 183 

Total insolubles 184 

Ether extractive 184 

Results of chemical examination, 1907 184 

Detailed chemical data on each permitted color 184 

Recalculation of analytical data on basis of coloring matter pres- 
ent 187 

Market quality of the seven permitted colors 190 



CONTENTS. 7 

Page. 

XV. Guides in detennining degree of purity and cleanliness 192 

XVI. Analyses of certified lots of permitted colors, 1909-10 198 

Tabulation of results 198 

Comparison of analyses made in 1907 201 

Conformity of analytical data with theoretical composition 202 

Arsenic determinations on 86 batches 204 

Suggested requirements for certified colors 205 

XVn. Methods of analysis used in testing colors for certification 210 

Introduction 210 

Naphthol Yellow S 211 

Ponceau 3R 215 

Orange 1 217 

Amaranth 220 

Light Green S F Yellowish 221 

Erythrosin 222 

Indigo disulphoacid 224 

XVm. Addenda 225 

Additional examination of coal-tar dyes 225 

Supplementary list of trade names of coal-tar colors 227 

XIX. Index of authorities quoted 227 



ILLUSTRATION 



Page. 
Fig. 1. Apparatus used in the determination of arsenic 213 



COAL-TAR COLORS USED IN FOOD PRODUCTS, 



INTRODUCTION. 
PURPOSE OF THE INVESTIGATION. 

For the purposes of the investigation reported in the following pages, 
the legitimacy of the coloring of food and food products under certain 
conditions is regarded as established ; the ethical and dietetic aspects 
of the question of food coloring are not here considered. 

The means at hand for coloring food products may be conveniently 
classified as vegetable, animal, mineral or inorganic, and synthetic 
or so-called coal-tar colors or dyes. Representatives of each of these 
have at one time or another all been used in the coloring of food, and 
the laws of various European and American States have, from time 
to time prohibited the use of certain specified members or all of each 
or some of the foregoing classes. It is therefore obvious that even 
for the legitimate purposes for which food can be colored, improper 
means are at command, and some of these, if not all, have been 
prohibited by law at some time or another. 

It is the function of the present work to determine what members 
of the synthetic or coal-car colors should be considered legitimate 
for coloring foods. It is confidently believed that the material 
collected in the following pages points clearly and solely to the 
following conclusions: 

1. Coal-tar dyes should not be used indiscriminately in foods. 

2. Only specified coal-tar dyes should be used in foods. 

3. Only tested and certified dyes should be used in foods. 

The work here reported has furnished the basis for Food Inspection 
Decisions Nos. 76, 77, and 106, issued July 13, 1907, September 25, 
1907, and March 25, 1909, respectively, and the investigation itself 
was practically terminated January 1, 1910. 

The effect of these decisions has been to restrict the coal-tar colors 
permitted for use in foods to seven specified and enumerated colors, 
until such time as it shall be shown with reasonable conclusiveness 
that other colors should be added to such list; and further, all coal-tar 
colors permitted for use in food are to be of a degree of purity and 
cleanliness acceptable to the Department of Agriculture, and are to 
be so certified. 

g 



10 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

In order to avoid any uncertainty as to the chemical composition 
of the enumerated colors, direct reference is made in Food Inspection 
Decision No. 76 to a standard work in which such chemical composi- 
tion is clearly and unequivocally set forth. The relevant parts of 
Food Inspection Decision No. 76 are as follows: 

The use of any dye, harmless or otherwise, to color or stain a food in a manner whereby 
damage or inferiority is concealed is specifically prohibited by law. The use in food 
for any purpose of any mineral dye or any coal-tar dye, except those coal-tar dyes 
hereinafter listed, will be grounds for prosecution. Pending further investigations 
now under way and the announcement thereof, the coal-tar dyes hereinafter named, 
made specifically for use in foods, and which bear a guaranty from the manufacturer 
that they are free from subsidiary products and represent the actual substance the 
name of which they bear, may be used in foods. In every case a certificate that the 
dye in question has been tested by competent experts and found to be free from 
harmful constituents must be filed with the Secretary of Agriculture and approved 
by him. 

The following coal-tar dyes which may be used in this manner are given numbers, 
the numbers preceding the names referring to the number of the dye in question as 
listed in A. G. Green's edition of the Schultz-Julius Systematic Survey of the Or- 
ganic Coloring Matters, published in 1904. 

The list is as follows: 

Red shades: 107. Amaranth. 56. Ponceau 3 R. 517. Erythrosin. 

Orange shade: 85. Orange I. 

Yellow shade: 4. Naphthol Yellow S. 

Green shade: 435. Light Green S F Yellowish. 

Blue shade: 692. Indigo disulfoacid. 

Each of these colors shall be free from any coloring matter other than the one 
specified and shall not contain any contamination due to imperfect or incomplete 
manufacture. 

The reasons, broadly considered, which led up to these food inspec- 
tion decisions are given in concise fashion in this introduction. 

Looking over the restrictions placed upon coal-tar colors by the 
lawmakers of the various countries it will be found that certain 
colors are in some instances specifically prohibited and in other 
instances that certain specific colors, or classes of colors, and only 
such, are permitted for the legitimate purposes of food coloring. 

Private organizations, such as the Swiss Society of Analytical 
Chemists and the National Confectioners' Association in the United 
States, have also made recommendations permitting specific colors 
only, and in addition specifically prohibiting others. Individual 
authors have likewise made similar recommendations. The control 
of the quality of the food colors practiced on the part of those Gov- 
ernments which restrict the use of coal-tar colors to certain individ- 
uals, so far as any publications show, has not been very extensive. 

The action taken against the use of coal-tar colors for food-coloring 
purposes has ranged all the way from absolute prohibition of their 
use for any purpose whatsoever to the practically unhmited use in 
legitimate food coloring operations of all but two of such colors. 



INTKODUCTION. 11 

Intermediate between these two extremes we find the prohibition of 
a greater number than two, or of all the members of this class except 
certain specified colors, and even here with the restriction that they 
shall be used only for certain legitimate food-coloring purposes. 

It would be desirable to have a number of coal-tar colors of estab- 
lished harmlessness specifically permitted, particularly if the number 
be sufficient to meet all the legitimate demands arising in the food- 
coloring art. To prohibit only specified coal-tar colors and, by 
implication, to permit all the rest of this class, would allow the 
unrestricted use of newly discovered colors, and all other coal-tar 
colors not examined as to their effect on health. A limited list of 
permitted coal-tar colors which would make the use of all coal-tar 
colors outside of the permitted list illegal would properly protect 
the health and could work no substantial hardship upon those 
engaged in food coloring. Any such hardship would be avoided by 
providing that if it is shown that none of the colors of the permitted 
list meets certain legitimate requirements and that coal-tar colors 
outside the permitted list are capable of satisfying this need and are 
in and of themselves harmless the permitted Hst can be expanded by 
the proper authorities to meet additional needs or growing require- 
ments without exposing the pubhc health to any risk. 

NUMBER OF COLORS PERMITTED. 

It will be shown in the following pages that in the summer of 1907 
there were on the market of the United States 80 different chemical 
individuals, or so-called coal-tar colors, offered for the coloring of 
food. It has been known since 1888 that it is unsafe to attempt 
to predict the harmfulness or the harmlessness of coal-tar colors by 
inference or analogy; therefore an ideally perfect permitted list should 
contain only such colors as have each been examined physiologically, 
separately, and specifically, and their harmlessness determined by 
actual test. Out of the 80 colors referred to 30 had not been exam- 
ined at all, so far as the literature shows, and therefore their harm- 
lessness is certainly open to question; 26 had been examined physi- 
ologically, and the published accounts with respect to their harm- 
lessness or their harmfulness are in each case contradictory; on 8 
none but adverse reports were to be found in literature, leaving 
only 16 out of 80 colors on the market which had been estabhshed 
with more or less certainty as harmless — that is, the users of these 8 
colors were deHberately taking chances with the public health, since 
the harmful nature of those 8 had for a long time past been known to 
those conversant with such subjects; the use of the 26 doubtful 
colors is more defensible than the use of the 8 known to be harmful. 
Out of the 30 of whose action nothing was known it can not be said 



12 COAL-TAK COLORS USED IN FOOD PRODUCTS. 

how many are or are not harmful, nor can the risk forced upon the 
pubKc health be satisfactorily measured. 

This brief summary must suffice for the present as a justification 
for the restrictions of the permitted colors to 7 in number. The full 
reasons for each and every step will appear in their proper places in 
the pages following. 

QUALITY AND EFFICIENCY OF COLORS PERMITTED. 

An examination of 30 specimens representative of the 7 selected 
permitted colors on the United States market in the summer of 
1907 disclosed such a condition of uncleanhness of product, or care- 
less or improper manufacture, and the use of such utterly inferior 
qualities of products for food coloring purposes, that control over 
the quality of the seven permitted colors seemed necessary. The 
results of the work in the making and maintaining of standards of 
quality for each of these seven colors also justify this control. That 
there was in 1907, and for a year or more later, a considerable diver- 
gence of opinion among chemists as to what should be the proper 
quahty requirements for these colors is shown by the fact that out 
of 72 foundation certificates offered in accordance with Food Inspec- 
tion Decisions Nos. 76 and 77, 57 were rejected on their face because 
they did not comply with the standards of quality then in mind, 
or then shown to be commercially attainable. Much objection has 
been made by many of those whose certificates were rejected on the 
ground that the standards then in mind were unreasonable, unjusti- 
fiable, and nonattainable. The actual results, however, are that 
with very few exceptions the standards in mind early in the work 
have all been exceeded in practice; the 41,000 pounds (20.5 tons) 
of certified colors now in existence made in 97 batches, or an average 
of more than 420 pounds per batch, are, with the exception of perhaps 
one or two first batches, far cleaner than was expected when the 57 
certificates above referred to were rejected. 

There has been no complaint against the permitted colors for want 
of efficiency or for the possession of unsuitable attributes, which has 
been pressed or sustained with any such earnestness as would rea- 
sonably be expected if the defects complained of were as great as 
they were represented. Complaints have been made against the 
yellow, when used in acidulated fruit sirups, on account of its pos- 
sessing a bitter taste ; the proof of this, so far as any has been offered, 
was for a long time not of a convincing nature, and it was two years 
after the first objection was raised before any concerted or positive 
action was taken by those interested. The yellow has also been 
criticized because it is not sufficiently fast to light; although it was 
satisfactorily shown that another yellow was faster to light than the 
permitted yellow, no one has maintained that the yellow desired 



INTEODUCTTON. 13 

was actually preferable to the permitted yellow wholly and solely 
because of its superior fastness to light. 

The blue has been criticized because it is not of the proper shade 
to permit of its use in the bluing of sugar, but the substitute offered 
therefor has not been supported by its sponsors in a way to indicate 
that a defect of serious magnitude exists. On the grounds of suffi- 
ciency and of efficiency the list of permitted colors selected appears 
to have been justified by the absence of any real or substantial com- 
plaint against them, on either or both of these grounds, during a 
period of more than three years. 

None of the seven permitted colors is patented ; their manufacture 
and their purification are open to all, and none of the 80 colors on 
the market in the summer of 1907, with perhaps one exception, had 
been discovered since 1891; in other words, the advances in the coal- 
tar industry from 1891 to 1907 had added nothing to the colors 
serviceable to the art of food coloring. 

The list of colors permitted in Food Inspection Decision No. 76 
embraces, therefore, a sufficient number of colors for all legitimate 
food-coloring purposes, the coloring of fats, oils, butter, etc., excepted, 
for which no suitable color had been examined and reported in the 
literature as being harmless and fit for use in foods ; they can be made 
by any one; no one can have a monopoly in any one of them by 
virtue of patents; any competent maker can make all or any of 
them and purify them to the required degree of cleanliness. The 
standards growing out of the control exercised by the Department of 
Agriculture are such as to insure that the colors used for food-coloring 
purposes possess a proper degree of cleanliness and such a degree of 
cleanliness is commercially feasible and is a commercial reality. 

The poHcy adopted in this respect is therefore justified not only 
from the viewpoint of the history of the attempts on the part of 
various governments to control the quafity of food colors, but also 
by the results actually obtained by its adoption. This policy of 
restricting food colors to certain chemical individuals and demand- 
ing that those possess certain qualities is in complete harmony with 
the following suggestion made to the commission on rules and regu- 
lations under the food and drugs act, at its hearing in New York, 
in September, 1906. 

Any kind of a harniless color should be permitted, provided it is not a color generally- 
known to be poisonous, or generally found to be poisonous, or one that may be almost 
impossible to be produced without containing some poison within itself when finished 
and ready for use. Coal-tar colors, as a class, should not be prohibited, but all those 
coal-tar colors generally found to be poisonous, or which are hard to produce without 
containing some poisonous properties when ready for use, should be forbidden the 
privilege of being used, or offered for sale for use in food. 

Under the provisions of section 2, we have this to recommend to the commission, 
that every person selling or using a coal-tar color in food or drink, should be required 



14 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

to secure, either on his own account, or from the person from whom he buys such color, 
a certificate to the effect that the identical color used has been tested for poisonous 
ingredients, and is, to the knowledge of the chemist making the test, absolutely harm- 
less. The chemist should be required to be a competent physiological chemist, and 
must certify as above under oath. This would mean not that each package of color 
would have to be tested, but that every batch would have to be tested, and the 
certificate would then be held to relate to every batch. Such tests should be made 
in the United States and the chemist certifying should reside in and be a citizen of 
the United States. 

It should not be deemed sufficient to have any particular brand of coal-tar color 
tested once, and a blanket certificate given, covering the whole brand as long as it may 
be sold, but every ounce of coal-tar color put out by a color manufacturer should be 
shown by actual test to be harmless. 

While the exact mode of reaching the end in view is somewhat dif- 
ferent from the one suggested above, yet the fundamental object, that 
each batch of color used in foods shall be specifically tested, and that 
such colors shall be harmless, is attained with reasonable certainty; 
and although there are colors other than these seven which are 
undoubtedly equally as little objectionable, and while it is true that 
the present policy contemplates the permitted use of but seven 
specific colors, yet that policy, as before outlined, is sufficiently broad 
and elastic to enable the addition of a color to the permitted list, 
when it is shown that such color really fills a need, not properly satis- 
fied by one of the colors already permitted or some combination of 
these, and is in and of itself harmless. There can be no objection to 
the expansion of the list to such an extent as to include every harmless 
coal-tar color in existence; but the burden of proving such real need 
and harmlessness is very properly placed upon those who are seek- 
ing such expansion. 

As far back as 1892 the following statement was made on page IV 
of the Leffmann translation of Weyl's book on coal-tar colors, in con- 
nection with the various European legislative enactments: ''It is 
certain that none of these plans is even approximately satisfactory 
and the problem will be even more difficult of solution in the United 
States; indeed, it seems to me to be unsolvable." In view of this 
opinion the results of the food inspection decisions as herein shown 
may properly be regarded as, at least, a step in. the right direction 
toward the solution of this problem. 

This opinion is further supported by C. A. Neufeld who, in review- 
ing Food Inspection Decision No. 76, says: ''The idea of permitting 
only specific selected coloring matters for use in the production of 
articles of food, and of excluding all other colors from such uses, must, 
in the interest of control of articles of food, be regarded as an extra- 
ordinarily happy one; a similar regulation is to be urgently recom- 
mended for our own country.'' {Zts. Nahr. Genussm., 1908, v. 15, 



IDENTITY OF COAL-TAR COLORS, 190*7. 15 

IDENTITY OF COAL-TAR COLORS USED IN FOOD PRODUCTS IN 
THE UNITED STATES IN 1907. 

COLLECTION OF SAMPLES. 

The question ^^ Which coal-tar colors shall be permitted for use in 
coloring such food products as are to be consumed within the United 
States?" can be answered, ''All colors now in use, or to be used for 
that purpose, provided they are harmless and necessary as defined on 
page 14." 

This involves the further questions : 

1. Which coal-tar colors of the 695 different chemical individuals 
now on the world's markets are actually used in the United States for 
that purpose ? 

2. If restricted to such coal-tar colors as are now in use in the 
United States for this purpose, would this be likely to hamper or inter- 
fere with the invention of other coal-tar colors suitable for the 
coloring of food ? 

It would be physically impossible to go to every user of coal-tar 
colors in food products in the United States and obtain specimens of 
the coal-tar colors so employed; this would be impracticable not only 
because of the large number of such users, and their wide geographical 
distribution, but also because they often do not know what they are 
using, and further because of a reluctance, undoubtedly to' be encoun- 
tered among many, to disclose the nature of the products employed. 
This is rendered more than hkely by the attitude of some of the 
makers of coal-tar colors, or their accredited agents, as will be shown 
later. 

However, the sources of coal-tar colors are limited in number. By 
reference to pages IX and X of ''A systematic survey of the organic 
coloring matters," by Arthur G. Green, pubhshed in London and New 
York by Macmillan & Co. (Ltd.), in 1904 (hereinafter referred to as 
*' Green Tables"), it mil be seen that there are approximately 37 
different concerns the world over engaged in the manufacture of coal- 
tar colors. Therefore a canvass of these sources for such coal-tar 
colors as in their judgment, or in their business practice, they regard 
as proper for use in food products, is the best way of arriving at a fair 
demarcation of the field of coal-tar colors here in question. 

Communication was therefore had with 13 actual manufacturers of 
coal-tar colors, in an endeavor to obtain from them such coal-tar 
colors as in their judgment or business practice are suitable for use, or 
are used in food products. 

A request was also made for information as to the chemical com- 
position of the coal-tar color specimens submitted ; in order to avoid 
confusion, it was further asked that reference be made to the Green 
Tables, in which each chemical individual or coal-tar color has its 



16 



COAL-TAR COLOES USED IN FOOD PRODUCTS. 



own number, and if any of the contributed specimens was not so listed 
that the chemical composition be stated in a manner analogous to 
that used in the Green Tables. This procedure was necessary in 
order to reduce the terminology to a common and nonequivocal basis. 
Out of the 13 makers, or their accredited sole importers or selling 
agents in the United States, who were consulted, 9 have supphed the 
specimens requested; the remaining 4 promised to contribute, but 
have not done so. In the following table is shown the amount and 
character of the information obtained: 

Tabulation of distribution of replies and character of information received. 





Geographical distribution. 


Number 
of 

samples 
contri- 
buted. 


Number 
of 

samples 
referred 

to 
Green 
Tables. 


Nvunber 

of 
samples 

not 
referred 

to 
Green 
Tables. 


No 


Country. 


Coal-tar 

color 
makers. 


Makers 

asked 

to send 

samples. 


Makers 

not 
sending 
samples. 


Makers 
sending 
samples. 


composi- 
tion or 
ambigu- 
ous ter- 
minology. 


Germany 


16 
8 
5 
5 
1 
1 
1 


6 
1 
1 
3 
2 




6 

1 


181 
12 


106 
12 


1 


74 


England 






France. 


1 
3 






Switzerland 












United States 


2 


61 


35 


5 


21 


Holland 






Belgium 












1 
















Total 


37 


13 


4 


9 


254 


153 


6 


95 


. 


" 



In order to make provision for the 24 makers listed in the Green 
Tables and not included in the 13 makers addressed requests for 
samples were sent to two domestic houses which import coal-tar colors 
from scources other than the above, for use in food products; their 
products must fairly represent any of the colors not covered by the 
13 makers addressed. Of these two importers, one responded with 
13 samples, and of each he gave the number in the Green Tables 
corresponding to each specimen ; the other importer has not redeemed 
his promise to contribute specimens. 

A third importer volunteered the Green Table numbers of four out 
of five coal-tar colors used in his business, but could not even approx- 
imately say what the remaining color was chemically. He did not 
contribute any specimens, nor was that necessary at the time this 
information was volunteered. 

A fourth importer contributed specimens of five coal-tar colors 
needed in his business, but was able to give Green Table numbers for 
only three of them ; he could not give even approximately the chem- 
ical composition of the remaining two. 

Out of the 1 7 responsible concerns consulted 5, or 29 per cent, have not 
found it to their interest to contribute either specimens or information. 



IDEITTITY OF COAL-TAR COLORS, 1907. 
CLASSIFICATION OF SAMPLES SUBMITTED. 



17 



GREEN TABLE NUMBERS. 

Out of the 284 specimens contributed, or reported on, 172 (60.6 
per cent) were identified as to their chemical composition, by refer- 
ence to the Green Tables; 6 (2.1 per cent) were otherwise unequivo- 
cally identified chemically, and for 106 (37.3 per cent) the makers, 
or their responsible agents, decHned to state the chemical composi- 
tion, i. e., 62.8 per cent were unequivocally identified, and the remain- 
ing 37.3 per cent were not so identified. 

The specimens submitted are therefore divisible into the following 
three classes: 

Class I. Those for which numbers were given in the Green Tables, 
numbering 172. 

Class II. Those whose composition was given in chemical language, 
numbering 6. 

Class III. Those whose composition was not given in any lan- 
guage capable of correct and certain translation into chemical terms, 
numbering 106. 

Consider Class I. The Green Tables, page VI, divide the coal-tar 
colors into 21 groups, comprising 695 different chemical individual 
coal-tar colors. The 172 members of Class I number in all 74 indi- 
viduals, or 10.6 per cent of the Green Tables, and fall into 11 of the 
21 groups of those Tables. 

The following table classifies the samples according to the Green 
Table groups: 

Green Table groups and number of collected samples falling within them. 



Color groups of the 
Green Tables. 


Number 
of mem- 
bers in 
group. 


Collected samples 
falling into the 
several groups. 


Color groups of the 
Green Tables. 


Number 
of mem- 
bers in 
group. 


Collected samples 
falling into the 
several groups. 




Number. 


Per cent. 


Number. 


Per cent. 


Nitro 


6 
126 
204 
46 
11 

5 
18 

8 

2 
66 
35 

6 


1 
30 
11 


16 
24 
5 


Anthracene 

Indophenol 


37 
8 

38 

32 
9 
6 
4 

21 
7 






Monoazo . . . 








2 


5 


Trisazo 


Oxazin. . 




Tetrakisazo 






Thiazin 


2 


22 




1 


20 






Stilbene 


Quinolin 


1 


25 








Sulphid , 




Diphenylmethane.. 
Triphenylmethane. 
Xanthene 


1 

15 
9 


50 
23 
26 


Indigo 


1 


15 






695 


74 


10.6 


Acridin . . 













97291°— Bull. 147—12- 



18 



COAL-TAR COLORS USED IN" FOOD PRODUCTS. 



SOURCE. 



The distribution of the 74 different chemical individuals of Glass I 
among the 12 different sources from which they were obtained is as 
follows : 

Distribution of the 74 different samples of Class I among the 12 sources supplying saime. 



Number. 


Per cent. 


Number 
of sources 
from 
which 
each 
came. 


Number. 


Per cent. 


Number 
of sources 
from 
which 
each 
came. 


35 
20 
4 
4 
5 
3 


47.3 

27 
5.4 
5.4 
8.1 
2.7 


1 
2 
3 
4 
5 
6 


1 
1 


1 




1.35 
1.35 


7 
8 
9 

10 
11 
12 


1.35 







It follows from this table that there is very little unanimity among 
the different concerns furnishing coal-tar colors for use in food prod- 
ucts as to which of their products are desirable, necessary, or suitable 
for such use. 

Inspection of this table shows that only tliree colors out of 74, 
or 4 per cent, were wanted by more than half of all the sources ; that 
only 6, or 8.1 per cent, were wanted by half of the sources; and that 
not one of the colors was wanted by all the sources. This last state- 
ment is true of manufacturers as well as importers, each group taken 
by itself. 

PATENTS. 

This lack of unanimity is not due to the patent situation, because 
not more than one of these 74 products is patented, and it is more 
than Hkely that the United States patent on this product has long 
since expired. 

Moreover, only 6 of the 12 sources offered colors at one time 
patented by themselves or others. The total number of such ex- 
patented products is 45, and of these only 22 were offered by those 
who had patented them; the remaining 23 were offered by sources 
other than the ex-patentees, and were not offered by such 
ex-patentees. 

Patented colors. 



Total num- 
ber of 
patented 
products 
offered. 


Ex-patented 
products 
offered by 
patentee. 


Total num- 
ber of 
patented 
products 
offered. 


Ex-patented 
products 
offered by 
patentee. 


11 
16 


7 


2 
8 
5 

4 


1 

4 


1 
2 


45 


22 



IDENTITY OF COAL-TAR COLORS, 1907. 



19 



It would, therefore, seem to be rather clear that others think more 
favorably of such ex-patented products as food colors than do the 
original patentees. In view of the fact that the latter would generally 
be in a better position, and would have greater opportunity than any 
one else to judge of the suitabihty of the patented products for use 
in food products, it may well be inferred that such products are not 
altogether free from disadvantages as food colors. 

The second of the two questions propounded, namely, If restricted 
to such coal-tar colors as are now in use in the United States for this 
purpose, would this be hkely to hamper or interfere with the invention 
of further coal-tar colors suitable for the coloring of food products ? 
can be answered ''No" because none of the colors submitted was 
discovered later than 1891; out of the 214 coal-tar colors since then 
discovered not one was among those submitted for use in foods, and 
out of the 481 discovered in 1891 and prior thereto, only 74 were so 
submitted, or 2 out of every 13 of such colors. In the following 
table these data are given year by year: 

Coal-tar colors discovered from 1740 to 1891. 



Year 
of dis- 
covery. 


Num- 
ber of 
sub- 
mitted 
colors 
discov- 
ered. 


Total 
num- 
ber of 
coal- 
tar 
colors 
discov- 
ered. 


Year 
of dis- 
covery. 


Num- 
ber of 
sub- 
mitted 
colors 
discov- 
ered. 


Total 
num- 
ber of 
coal- 
tar 
colors 
disco-^- 
ered. 


Year 
of dis- 
covery. 


Num- 
ber of 
sub- 
mitted 
colors 
discov- 
ered. 


Total 
num- 
ber of 
coal- 
tar 
colors 
discov- 
ered. 


Year 
of dis- 
covery. 


Num- 
ber of 
sub- 
mitted 
colors 
discov- 
ered. 


Total 
num- 
ber of 
coal- 
tar 
colors 
discov- 
ered. 


1740 
1856 
1859 
1861 
1862 
1863 
1867 


1 
1 
1 
2 
1 
1 
1 


1 
3 
1 
3 
5 
3 
3 


1871 
1874 
1875 
1876 
1877 
1878 
1879 


1 
1 
6 
5 
2 
12 
7 


6 
4 
12 
9 
10 
26 
23 


1881 

1882 
1883 
1884 
1885 
1886 


4 
5 
9 
3 
2 
3 


11 
20 
25 
16 
21 
32 


1887 
1888 
1890 
1891 

Total. 


1 
1 
1 
3 


29 
36 
46 
33 


74 


378 



SHADES OF COLOR. 

The sufficiency of the 74 colors used for food-coloring purposes in 
the United States, for any and all tinctorial ranges, no matter how 
refined, appears from the following table: 

Green Table numbers of the 74 submitted colors showing shades and number of sources 

supplying each. 





Shades. 


Number of sources out of a possible 12 offering each color. 


Total 
number 




1 


2 


3 


4 


5 


6 


7 


8 


9 


10 


of dyes 
offered 
for each 
shade. 


Red 


104 
105 
169 
240 
584 


65 
108 
146 
462 






106 


103 


107 








12 
















































































20 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



Green Table numbers of the 74 submitted colors showing shades and number of sources 

supplying each — Continued. 





Number of sources out of a possible 12 offering each color. 


Total 
number 


Shades. 


1 


2 


3 


4 


5 


6 


7 


8 


9 


10 


of dyes 
offered 
for each 
shade. 


Blue red 




502 
518 
520 
523 

512 




448 


504 
517 












7 




54 
516 

53 

64 

56 

89 
269 
329 

9 




















































Yellowish red 


















3 






















Scarlet 


55 


















3 






















Bluish scarlet 




















1 


YeUow 






510 


8 


94 








4 


7 






































Reddish yeUow. . . 


84 
14 

17 
85 
95 

650 


















2 


Orange yellow 








13 










2 


Greenish yellow 


667 

18 
97 

439 
476 
480 
655 

440 

468 

464 

287 

433 
434 


425 














2 


Orange 










86 






6 








































Blue 


692 
















6 
















































■'■- 
















Green blue 




















1 


Violet 


452 






451 












3 


Blue violet , 
















1 


Grayish violet . . 




















1 


Green . . 


398 




435 














4 




















427 


















1 


Yellow green 




428 
















1 


Brown. 


101 
137 
139 


















3 














































Reddish brown 


201 




197 














2 


Blue black 


188 
601 














1 


Blue to bluish red to violet, 
according to brand 




















1 
























Oil-soluble colors . 


10 
49 
60 


11 


















4 






















Total 














































35 


20 


4 


4 


5 


3 


1 


1 




1 


74 



The six colors comprising Class II (those not listed in the Green 
Tables but whose composition was avowed or disclosed) are one 
black, one yellow, and one orange among the water-soluble colors, 
and three yellows among the water-insoluble colors. Therefore two- 
thirds of the United States market as thus disclosed calls for a total 



IDENTITY OF COAL-TAR COLORS, 1907. 



21 



of 80 different chemical individuals, of which 73 are water-soluble and 
7 are water-insoluble and are used as oil or fat colors. The remain- 
ing third of the makers or dealers either do not possess the information 
or are unwilling to give it. No attempt has yet been made to enter 
systematically into this unknown region, but careful examination 
warrants the belief that it can add nothing of material value to 
the data already obtained which show a total of 23 shades for the 
73 water-soluble coal-tar colors, summarized as follows: 



Number of coal-tar colors. 



5 red shades 26 

4 yellow shades 14 

1 orange shade 7 

2 blue shades 7 

3 violet shades 5 



3 green shades 6 

2 brown shades 5 

1 blue-black shade 1 

1 black shade 1 

1 blue to violet shade 1 



The water-insoluble colors numbering 7 are not included, but will 
be treated separately (p. 159). 

This view of the state of the United States market at or about the 
middle of the year 1907 is without question a true reflection of that 
market as far as it goes and the actual extent of the coal-tar color 
market beyond those covered by this canvass of it is not likely to be 
very great. In support of this view is the interchangeable treatment 
of formerly patented products, the great lapse of time since a new food 
color was discovered, and the fact that out of the 74 colors submitted 
and contained in the Green Tables only 23 are now less than 25 years 
old, and none is less than 16 years old. 

All the Green Table numbers and the number of sources out of a 
possible 12 offering them are given in the following table: 



Number of sources, out of a possible 12, offering colors designated in 1907. 



Green 




Green 




Green 




Green 




Table 


Sources. 


Table 


Sources. 


Table 


Sources. 


Table 


Sources. 


No. 




No. 




No. 




No. 




14 


10 


86 


s 


240 


1 


476 


1 


8 


5 


89 


1 


269 


1 


480 


1 


9 


1 


94 


6 


287 


1 


502 


2 


10 


1 


95 


2 


329 


1 


504 


5 


li 


2 


97 




398 


2 


510 


4 


13 


6 


101 




425 


3 


512 


3 


14 


2 


103 




427 


2 


516 


1 


17 


2 


104 




428 


3 


617 


5 


18 


1 


105 




433 


1 


518 


2 


49 


1 


106 




434 


1 


520 


2 


53 


1 


107 




435 


4 


523 


2 


54 


1 


108 




439 


1 


584 


1 


55 


2 


137 




440 


1 


601 


1 


56 


1 


139 




448 


4 


650 


2 


60 


1 


146 




451 


5 


655 


1 


64 


1 


169 




452 


2 


667 


1 


65 


2 


188 




462 


2 


692 


3 


84 


2 


197 




464 


1 






85 


2 


201 


2 


468 


' 







Italicized figures indicate colors permitted by F. I, D. 76. 



22 



COAL.-TAK COLORS USED IN FOOD PRODUCTS. 



Nine manufacturers sent 261 specimens, an average of 29 each, 
distributed as follows: 70; 38; 20; 20; 15; 43; 25; 18, and 12. , Two 
importers sent 5 specimens each, and one 13, a total of 23 specimens, 
and an average of 8. These figures reflect a diversity of opinion as 
to what is needful for food coloring, since each one of these 12 makers 
or importers beheved that for all practical food-coloring purposes 
his selection was complete and sufficient. 

Classifying the 284 specimens as red, yellow, brown, orange, blue, 
green, violet, and black, the following table is obtained showing the 
different requirements of each of the 12 makers or importers to 
produce the necessary shades of the eight colors mentioned: 

Total specimens submitted, grouped hy makers and colors, showing number of shades 

required by each. 



Maker's 
number. 


Red. 


Yel- 
low. 


Brown. 


Orange. 


Blue. 


Green. 


Vio- 
let. 


Black. 


Number 

of 
sliades 
wanted 
by each. 


Total 
speci- 
mens. 


1 


25 

10 
7 

11 
6 
4 
6 
5 
6 

13 
3 
3 


18 
6 
5 

10 
2 
3 
2 
4 
4 

10 
1 
1 


14 
2 

io' 

2 

1 

i' 

2 


4 
1 
2 
5 
3 
1 
2 

1 
3 
3 

1 


2 
3 
1 
2 
4 
3 
1 
1 

5' 


5 
1 
1 
2 
2 
1 


2 
2 
1 
3 
2 

1 


i' 

i' 


7 

5 
6 
6 

7 
3 
3 


70 
25 
18 
43 
20 
15 
12 
13 
20 
38 
5 
5 


2 


3 


4 


5 


6 


7 


8 


1 
4 
4 


1 
2 

1 




9 


10 


11 


12 




1 






Total.... 

Per cent 

Maximum.... 
MinimiTrn 

Average 

Permitted.... 












99 
34.86 
25 
3 
8.25 
3 


66 

23.24 

18 

1 

5.50 

1 


32 

11.27 

14 


26 

9.15 

5 


22 

7.75 

5 


22 

7.75 

5 


15 

5.28 

3 


2 
0.70 

1 




284 
100 










2.75 


2.17 
1 


1.83 
1 


1.83 
1 


1.25 


0.17 



















From this table it appears that not one of the 12 sources desired all 
of the 8 shades into which the 284 specimens are classifiable to make 
up a complete set of food colors; 7 out of the 12 sources wanted 7 of 
the 8 shades ; 2 sources wanted 6 out of the 8 shades ; 1 source wanted 
5 of the 8 shades, and 2 sources were content with 3 out of the 8 
shades. 

It will be noticed that the permitted list given in Food Inspection 
Decision No. 76 provides for 7 dyes covering 5 out of the 8 shades of 
the above classification. The 3 missmg shades are brown, violet, 
and black; the shades provided are red, yellow, orange, and blue. 

It will also be noticed that on the whole 6 out of the 8 shades were 
not wanted by one or more of the 12 sources. The italicized shades 
are the ones not provided for by the permitted list of Food Inspection 
Decision No. 76. 

Brown was not wanted by 5, nor orange by 1, blue by 3, green by 2, 
violet by 3, nor hlaclc by 10. 



PUEPOSES OF FOOD COLORING. , 23 

The combinations not wanted were as follows : Five sources omitted 
hlack only; 2, hrown only; 1 blue and Hack; 1 hrown and Hack; 1 
green, violet, and Hack; and 1 hrown, blue, green, violet, and Uack. 

Not one of these 12 sources wanted only the three colors not found 
on the permitted list, and 2 sources did not want any of the three 
missing shades nor two of the permitted colors. 

In view of this large difference of opmion among the 12 sources as 
to the shades needed to make a complete set of food colors, the 5 
shades selected for the permitted list of Food Inspection Decision 
No. 76 seem reasonably close to any consensus of opinion derivable 
from the tabulation of the collected facts. 

II. PITRPOSES OF FOOD COLORING. 

The use of any color which conceals inferiority, or which gives an 
article an appearance better than it properly possesses is, of course, 
illegitimate, and such cases are not here considered. Among such 
uses may be mentioned that of color in pastry to impart a yellow 
color thereto, implying the presence of eggs, when they are either 
wholly absent or are not present in sufficient quantities to produce a 
shade of color which would indicate a superior quality. Such color- 
ing is frequently resorted to in macaroni, spaghetti, noodles, and the 
like, and it has also been stated in the literature that such coloring 
has the additional function of concealing dirt actually present in the 
flour. 

The addition of red coloring matter to meat products to give them 
an appearance of freshness which they do not of themselves possess ; 
the addition of red coloring matter to strawberry, raspberry, and 
similar jams, jeUies, and preserves, to give them a color indicative of 
exceptional quality, even though they may contain none of the fruit 
whose presence is intimated by the label on the product; the injection 
of red coloring matter into ordinary oranges to give them the appear- 
ance of blood oranges; the sprinkling of lemons and oranges with 
green coloring matter to give them the appearance of a particular 
origin or of a particular state of ripeness when such origin or state of 
ripeness is without foundation in fact; the injection of red coloring 
matter into watermelons to give them the appearance of ripeness, 
which ripeness they do not possess, are practices met more or less 
frequently. 

Among the purposes for which food colors are said to be used and 
the foods so colored, the following are mentioned in the literature : 

In European countries. 

1. Macaroni is colored with. Dinitrocresol (2) (Arch. Pharm., 3d ser., v. 22, p. 621) 
and Martins Yellow (3) (Weyl, Handhuch). 

2. Cordials and liqueurs with Dinitrocresol (2) {Arch. Pharm., 3d ser., v. 22, p. 621). 



24 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

3. Oranges: Biebrich Scarlet (163) (Weyl, Handbuch). 

4. Pastry: Dinitvocresol (2) {JVeyl, Handbuch). 

5. Butter: Dinitrocresol (2) {Weyl, Handbuch). 

6. To whiten flour: Anilin blue (457) {Zts. Nahr. Genussm., 1906, v. 12, p. 298). 

7. Noodles are colored to cover up cigar butts, burnt matches, mineral oil, etc. 
{Zts. Nahr. Genussm., Vol. II, p. 1018). 

In the United States. 

8. Jellies, fruit sirups, soda sirups, jams, ketchup, cheap cordials, lemon extract, 
milk, butter, cheese, ice cream, confectionery, pastries, flavoring extracts, mustard, 
cayenne pepper, sausage, noodles, wines, and liqueurs {Winton, Connecticut Agricul- 
tural Experiment Station Report, 1901, pp. 179-182). 

9. Cattle feed is colored yellow {Gudeman, J. Amer. Chem. Soc, 1908, v. 30, p. 1623). 

10. "Egg color" (399); "Macaroni color" (94); "Tomato catsup color" (105); 
"Raspberry color" (103); "Mustard color" and "Pie filling color" (4); "Orange 
color" (87), and "Strawberry red color" (55) are corresponding United States com- 
mercial food color names and their corresponding Green Table numbers {Meyer, J. 
Amer. Chem. Soc, 1907, v. 29, p. 895). 

Dr. E. Ludwig, of Vienna, stated, upon the authority of Dr. 
Schacherl, at the International Congress of Medicine held in Budapest, 
in August, 1909, as follows: 

The rather widely distributed practice of coloring baker's goods yellow, such as 
cakes and the like, further the yellow coloring of pastry, macaroni, noodles, and so 
forth, has as its function the representation of a very large egg content in them; this 
coloring has been made very convenient because there are in commerce colors intended 
specifically for this purpose and designated "egg substitute" and which have nothing 
whatever in common with egg yolk. 

Marmalades such as apricot, raspberry, and currant marmalades are frequently found 
in a colored condition in commerce; in this case the purpose of the coloring is frequently 
to cover up adulteration; the adulteration may consist in an admixture of a cheap 
fruit pulp, particularly apple pulp, or in an addition of glucose sirup. Since these 
admixtures do not possess the color of the marmalades they are simply helped along 
by the aid of color. 

Old fruit sirups are toned up with color and then sold as fresh sirup. 

Red colored fermentation vinegar and red colored vinegar essence as well as vinegar 
made from such essence are in commerce; such coloring has for its purpose to represent 
the product as "genuine red wine vinegar," which in some countries is highly desired. 

So-called "beer color," said to be an extract of roasted malt (malt caramel), is in fact 
nothing but ordinary sugar caramel and is frequently from time to time publicly adver- 
tised; breweries themselves do not use this preparation, but it has been frequently 
shown that in small taverns by means of this color local beer was converted into 
Bavarian beer. 

The wholesale coloring of coffee beans serves the purpose of representing a better 
quality than it actually is. 

The coloring of cocoa and chocolate by the use of mineral additions and also of coal- 
tar colors was often proven; in this case the coloring serves exclusively to cover up 
poor quality. In the case of good products such coloring is not practiced. 

Colored sausages, and iq fact such with a colored meat body as well as such with a 
colored casing, are frequently colored; coal-tar colors and cochineal serve this purpose, 
the latter, however, only for the meat. This coloring is to preserve in old goods the 
appearance of fresh goods. 

The green canned goods of commerce are almost all colored with copper compounds. 



FOOD-COLOR REQITIREMENTS. 26 

Tomato pulp frequently comes into commerce colored with a coal-tar color; the pur- 
pose of such coloring is to impart to the goods the appearance of having been prepared 
with extraordinary care. In all these cases it is not at all a question of a harmless 
change of the natural condition of the food product, but of improper manipulations 
which are adapted to deceive the purchaser as to the real value of the goods; even, 
indeed, to mask the danger to health. 

III. FOOD-COLOR REQUIREMENTS. 
ADAPTABILITY FOR SPECIAL PURPOSES. 

Not all coal-tar colors are adapted for use in food products. 
Colors are the more desirable for this purpose the higher their tinc- 
torial power, and the greater the resistance they offer to the action 
of the materials with which they are to be used, and under the con- 
ditions existing. Obviously only such colors as of themselves have 
their tinctorial properties fully developed can be used, and all such 
colors as require a mordant to develop or bring out the color are not 
fit for nor capable of use in food products. 

Further, if the colored material is subjected to varying tempera- 
tures in the process of manufacturing foods, it should be able to 
withstand the effects of such temperatures, as, for example, in the 
manufacture of candies. The colors should also withstand the action 
of reducing agents, such as are generated in the course of fermenta- 
tion and decomposition of the food product, or where a preservative 
such as sulphur dioxid is added to the food product to minimize the 
effect of decomposition of the food upon the color. Such colors are 
put on the European market, and perhaps, but not necessarily, 
on the United States market with preservatives added to them. 
Most of the coal-tar colors are susceptible to the action of sulphur 
dioxid, particularly when the latter has been used in the decolor- 
izing of glucose, and Uranin (510) is one of the colors found to have 
the greatest resistance to the sulphur dioxid which may remain 
combined in candy. 

For example, the book entitled ''Henley's Twentieth Century 
Book of Receipts, Formulas and Processes," published in 1907, on 
page 359, says of sausage color: 

It is absolutely necessary in using aniline colors to add a disinfectant to the dye- 
stuff solution, the object of which is, in case the sausage should commence to decom- 
pose, to prevent decomposition of azo-dyestuff by the disengaged hydrogen. Instead 
of boracic acid, formaline may be used as a disinfectant. 

J. Fraenkel {Arbeit. Kaiserl Gesundh. 1902, v. 18, pp. 518-521; 
abst. Zts. Nahr. Genussm., 1902, v. 5, p. 986) reports as follows on 
the composition of colors used in coloring sausages, meats, and 
preserves : 

1. Blood color: Moisture, 15 per cent; common salt, 6.6 per cent; borax, 21 per 
cent; and Ponceau 2 R (G. T. 55). 



26 COAL-TAR COLOES USED 12^ FOOD PRODUCTS. 

2. Blood red for meat juices: Liquid of a specific gravity of 1.0163 not affected by 
acids or alkalis and containing 27 per cent total solids; of these total solids 31 per cent 
were salt, 12 per cent borax, and the remainder Ponceau 2 E, (G. T. 55). 

3. Casing red: This powder contained Orange II (G. T. 86). 

4. Sausage red: A liquid containing Eosin. 

5. Lobster color: A liquid of specific gravity 1.0064 containing 1.64 per cent of 
solids, of which 10.9 per cent were salt and the remainder Ponceau R T (G. T. 44). 

G. Possetto {Zts. Nahr. Unters. Hygiene Waarenk. 1891, v. 6, 
p. 105) cited the following 15 colors as being used for the coloring 
of pastry: 

G.T.No. 

Martins Yellow 3 



G.T.No. 

Tropgeolin 00 88 

Tropgeolin 000 No. 1 85 

Tropseolin 000 No. 2 86 

( -^^ 

Chrysoidin \ 18 

[ 41 

Azoflavin 92 



Victoria Yellow 2 

Naphthol Yellow S 4 

Aurantia Yellow 6 

Acid Yellow G 8 

Acid Yellow R 9 

Citronin 91 

Tropseolin 84 

Algerian Saffron (a mixture of Nos. 4 and 86 and crocein). 
Prussian Saffron (composition not given). 

"Blood-red'' on the American market is starch colored with red coal-tar colors 
{Ibid., 1896, V. 10, p. 114). 

''Butter yellow" is a clear saponifiable oil of reddish-yellow color, containing 
3 per cent of anilin-azo-dimethylanilin (No. 16 of the Green Tables). 

PROPORTION OF COAL-TAR COLOR USED. 

The amount or proportion of coal-tar color used has been variously 
stated. On page IV of the Leffmann translation of Weyl's book 
entitled '^The Sanitary Relations of the Coal-Tar Colors," it is 
stated that 1 ounce of Auramin (G. T. 425) will color 2,000 pounds 
of confectionery, which means 1 part of color in 32,000 parts of 
colored product. 

Frentzel (Zts. Nahr, Genussm., 1901, v. 4, pp. 968-974), on author- 
ity not given, says that for sirups 1 part of color is used to from 
4,000 to 5,000 parts of sirup; in colored sugars 1 part of coloring 
matter to from 1,333 to 4,000 parts of sugar; and in flour 1 part of 
coloring matter to from 666 to 1,000 parts of flour. 

In pastry 1 to 100,000 parts {Zts. Nahr. Unters. Hygiene, Waarenk. 
1893, V. 7, p. 34). 

In chapter VII (p. 47), sections 15, 16, 17, and 18, are brought 
together statements made before the commission on regulations for 
the Federal food and drugs act, as to the amount of color contained 
in colored food products. Briefly these are as follows: Confec- 
tionery, 1 part of color in 3,500 parts of product; beverages 1 part 
of color in 128,000 parts, 256,000 parts, 1,024,000 parts; butter, 420 
grains of color to 1,000 pounds of butter; or 1 part of color to 
16,666 parts of butter. 



FOOD-COLOR REQUIREMENTS. 



27 



One ounce of color to 30 pounds of ''colored food;" the colored 
food was not further defined; which means 1 part of color in 480 
parts of colored product. 

It has further been represented that 1 part of color is sufficient 
to whiten 250,000 parts of yellow sugar. 

From time to time others have presented information as to the 
amount of color used in food products. All of these data available 
have been tabulated, showing the number of parts of colored product 
containing 1 part of coal-tar color, arranged in the order of the 
amounts present: 

100 Confectionery 24,576 

480 Do 30,000 

666 Do 32,000 

1,000 Beverages 80,000 

1,333 Pastry 100,000 

3,500 Beverages 120,000 

4,000 Do 128,000 

4,000 Confectionery 192,000 

5,000 Whitening sugar 250,000 

12,800 Beverages 256,000 

16,666 Do 1,024,000 

20, 000 



Food 1 

Do2 

Flour 

Do 

Sugar 

Confectionery. 

Sirups 

Sugar 

Sirups 

Confectionery. 

Butter 

Confectionery. 



Grouped according to the kind of material colored, the ranges 
given are as follows: 



Beverages 80, 000 ; 

120, 000; 128, 000; 
256,000; 1,024,000 

Butter 16, 666 

Confectionery 3, 500 

12, 800; 20, 000 
24, 576; 30, 000 
32,000; 192,000 

Flour 666; 

1,000 



Food UOO; 

2 480 

Pastry 100, 000 

Sugar 1, 333; 

4,000 
Sirups 4, 000 ; 

5,000 
Whitening sugar 250, 000 



These statements have emanated from persons presumably ac- 
quainted with the facts of their own practice, and if that presumption 
is correct it appears that there are wide variations in practice not 
only among individual users, but for individual colors. No attempt 
has been made to prove or disprove these statements by actual deter- 
mination of the amount of color contained in commercial colored 
food products. 

The 80 chemical individuals on this market for food-coloring pur- 
poses, it can be fairly assumed, have been tested and tried out as to 
their utifity, and in tliis respect further tests were regarded as super- 
fluous and therefore have not been undertaken. 



1 Kind not definitely stated. 



2 Said to be for preserved tomatoes. 



28 COAL-TAR COLOES USED IN FOOD PRODUCTS. 

SUITABILITY OF SHADES OF PERMITTED COLORS AND MIXTURES 

OF SAME. 

. The shades produced by the seven permitted colors are, respec- 
tively, yellow, orange, blue, green, red, bluish scarlet, and brilhant 
cherry red. As statements are found in the hterature against the 
use of all of the chemical individuals producing a brown or a violet 
shade, it will be necessary to produce these shades by a proper com- 
bination of two or more- of the permitted colors. So far no criti- 
cism with regard to the shades produced by the seven colors them- 
selves and by their appropriate mixture has been made that has been 
substantiated. 

Objection has been made to the violet producible from blue and 
red, on the ground that when applied to a food product, such as 
candy, the component parts do not evenly fix themselves upon the 
material. This objection, however, has not been pressed and proba- 
bly is not well taken, because of the fact, frequently reported, that 
few, if any, coal-tar colors are used without admixture of one or more 
other colors to shade or to tone the original color. This criticism, 
therefore, of the use of mixed colors can be regarded as not a serious 
objection. 

One criticism urged with considerable persistency against the seven 
permitted colors was that none of them would withstand the action 
of the organic acids ordinarily found in beverages such as lemonade, 
and it was suggested that no color was proper for use for such pur- 
poses which would not withstand, unaltered, for a period of 12 hours 
the action of a 10 per cent solution of citric acid. In urging this 
objection substitutes were suggested for the permitted colors. The 
substitutes so urged were Tartrazin (94), Azorubin (103), Orange 
II (86), Ponceau 4 GB (13), and one other color designated as Scarlet 
SE, of whose chemical composition no information whatever was 
forthcoming. (The numbers in parentheses refer to the Green Tables.) 
Of the five colors suggested it can be said that concerning all but No. 
103 adverse statements are found in the literature, and No. 86 is spe- 
cifically regarded by every observer but one as being thoroughly 
poisonous. The suggested substitute list is, therefore, objectionable 
on the ground of injuriousness to health. 

To test the validity of the assertion that none of the permitted 
colors could withstand the action of citric acid, solutions of the sug- 
gested colors, as well as of the permitted colors, each one in a thou- 
sand, were submitted to the action of citric acid, added in such quan- 
tity that it amounted to 10 per cent of the total bulk of solution. 
This experiment showed that Tartrazin is reddened by citric acid, 
whereas Naphthol Yellow S loses in tinctorial power to a slight extent. 
The shade produced by Ponceau 4GB can be closely imitated by a 
mixture of Naphthol Yellow S, Orange I, and Amaranth, all per- 



FOOD-COLOR EEQTJIREMENTS. 29 

mitted colors. There is no choice whatever in the shade produced 
by the desired Azorubin and the permitted Amaranth, nor is there 
any difference in behavior toward citric acid. The difference in the 
shade between the desired Orange II and the permitted Orange I is 
so small that it requires a side-by-side comparison to distinguish 
between them. Moreover, the desired Orange II produces a precipi- 
tate when brought in contact with the citric acid, whereas the per-, 
mitted Orange I does not so precipitate. The permitted Erythrosin 
is, of course, completely precipitated by the citric acid. The per- 
mitted Light Green and Indigo disulphoacid are weakened in tinctorial 
power by the addition of the citric acid. Of these colors the only 
ones used to any extent in beverages, so far as either the suggested 
or permitted list is concerned, are red, yellow, green, and orange. 

As has been shown the permitted reds equal the desired reds and 
the permitted orange is better than the desired orange. The tinc- 
torial power of the permitted yellow is not so great as the tinctorial 
power of the desired yellow, but this difference is so slight that the 
objection urged against the list of permitted colors, namely that they 
were so poor in quality that they had destroyed a profitable and 
lucrative business in the coloring of beverages, is untenable in view 
of the fact that, assuming a price of $1 per pound for Tartrazin, and 
40 cents for Naphthol Yellow S, and using them in the proportions 
necessary to produce a lemonade color in a 10 per cent citric acid 
solution, it would take 5,000 quarts of finished lemonade to cause 
an increase of 1 cent in the cost of the production of the colored 
food product; that is, it increases the price per quart by one 
five-thousandth of a cent. 

It has also been urged that the permitted green is not good enough 
for cordials and liqueurs, and that it is impossible to bring about the 
proper green by the use of the permitted yellow and blue. This criti- 
cism, however, has not been persisted in; the fact is that mixtures of 
the permitted yellow and blue can be made so as to obtain any desired 
shade of green, having a yellow or blue cast, and great clarity and 
brilliancy. How these mixed colors would look after a long period 
of time has not been ascertained. 

It has also been said that the permitted red. Amaranth, is not a 
color suitable for the coloring of strawberry jams and it has been urged 
that the same chemical individual under another commercial name 
is better than the permitted red. This criticism has not been pressed, 
probably for the reason that it can not be substantiated. 

Again it was claimed that the deposits to be noticed in bottled 
lemonades were due to Naphthol Yellow S, but solutions of Naphthol 
Yellow S in citric acid have remained without deposit for upward of 
15 months; it is possible that such precipitation, if observed, may be 
due to an admixture of the nonpermitted Orange II with Naphthol 



30 COAL-TAR COLOES USED IN FOOD PRODUCTS. 

Yellow S, and this dfficulty can be obviated by the use of the per- 
mitted Orange I, which does not precipitate in the citric acid, as 
shown. 

Naphthol Yellow S has been objected to on account of the bitter 
taste it is said to impart to the beverages to which it is added, and 
steps have finally been taken by those interested to have another 
yellow placed on the permitted list. 

It has also been objected that the permitted blue is not suitable for 
the coloring of sugar, first, because it is soluble, and second, because 
of the unsatisfactory shade. It may be sufficient, in answer to this 
criticism, to state that there was no insoluble blue offered on this 
market, and there was no blue other than the one permitted offered 
against which adverse statements did not exist in the literature, and 
in view of this state of affairs the criticism may be said to be not well 
taken. 

As against all these specific criticisms it has been repeatedly stated 
by those in a position to know that they have found no difficulty 
whatever, by suitable mixtures of permitted colors, in reproducing 
any desired shade of any desired quality, not even excepting browns 
and violets. 

Considering all of these criticisms, therefore, the conclusion seems 
reasonable that there is no serious or permanent objection to be made 
against the seven colors selected, either as to qualities for food- 
coloring purposes or range of producible shades. 

IV. CONFORMITY OF FOOD-COLOR MARKET, 1907, TO RECOM- 
MENDATIONS OF THE NATIONAL CONFECTIONERS' ASSOCIA- 
TION, 1899.1 

Having thus shown that the food-color market of the United States 
contains not less than 80 coal-tar colors which are distinct chemical 
individuals, of which 74 are entered in the Green Tables and 6 are 
not, the next question to be considered is whether all of these sub- 
stances are harmless and fit for use in food products. 

As a guide in determining this point the '^ Official circular from the 
executive committee of the National Confectioners' Association of the 
United States," pertaining to colors in confectionery , dated February 1, 
1899, may well be considered. 

The function of this circular is said to be 'Ho throw light upon the 
vexed question of what colors may be safely used in confectionery," 
evidently because ' ' there may at times be a doubt in the mind of the 
honest confectioner as to which colors, flavors, or ingredients he may 
safely use and which he may reject." 

The circular also states that "but infinitesimal amounts of color 
(coal-tar colors) need be or can be used to give the desired effects," 

1 See also p. 45. 



FOOD-COLOR REQUIREMENTS. 



31 



and in view of this statement as to quantity it must be self-evident 
that a color harmful when used in the small quantities said to be used 
in confectionery is certainly harmful when used in the large quantities 
used in coloring other food products. This circular under the head- 
ing, ''Colors that are injurious and therefore to be rejected — Harm- 
ful organic colors," enumerates 21 coal-tar colors. Of these 21 colors, 
13, or 61.9 per cent, were among those submitted, and whose com- 
position was stated by reference to Green Table numbers; the Green 
Table numbers of these colors, together with the number of sources 
from which they were obtained, follow: 



Green 

Table 

numbers. 

11-... 

17.... 

18 

84.... 

86.-.. 

95-.-. 

106-..- 



Number 
of 



Green 

Table 

numbers. 

169 



197. 
201. 
398. 
584. 
650. 



Number 

of 
sources. 



Out of these 13 colors 3 each came from one source; 7 each came 
from two sources; 1 came from four sources; 1 came from five 
sources, and 1 came from eight, sources, out of a possible 12; that is, 
one was wanted by more than half the sources. 

It is further to be noted that of the trade names given to the sub- 
mitted products of Class I the following appeared among the harmful 
list of this circular and also were found in identical form and spelHng 
on the labels of the submitted products: 



1. Bismarck Brown. 

2. Chrysoidin R. 

3. Chrysoidin Y. 

4. Mandarin G extra. 

5. Naphthol Green B. 

6. Napthol Yellow. 

7. New Coccine. 



8. Orange A. 

9. Orange A extra. 

10. Orange G. 

11. Orange II. 

12. Scarlet. 

13. Vesuvin B. 

14. Crocein Scarlet 5 B. 



The following parallel will serve to show the great resemblance 
between the names given to the harmful colors of the circular and 
those found on the samples submitted: 

Circulars harmful list. Labels of submitted samples. 

Methylene Blue B B Methylene Blue B. 

Methylene Blue B B crystals 1 . . Methylene Blue D. 

Methylene Blue B B G Methylene Blue 0. 

Methylene Blue DBB 

New Coccine New Coccine O Z. 

New Coccine Z. 

Naphthol Green B Naphthol Green. 



32 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Circular's harmful list. Labels of submitted samples. 

Orange II Orange II Z. 

Victoria Yellow Victoria Yellow Cone. Z. 

Victoria Yellow Cone. T Z. 

Acid Yellow Acid Yellow G. 

Bismarck Brown G Bismarck Brown B. 

Bismarck Brown T Bismarck Brown B 216. 

Bismarck Brown Dark. 

Bismarck Brown R X. 

Bismarck Brown T D. 

Bismarck Brown Y Bril. 

Bismarck Brown Y Dark. 

Bismarck Brown 2 R X. 
Chrysoin Chrysoin Brown G Z. 

Chrysoin G E Z. 

Chrysoin R E Z. " 

Chrysoin R Z. 

Cochineal Red A Cochineal Red. 

Crocein Scarlet 3 B Crocein Scarlet 10 B. 

Crocein Scarlet 7 B 

Crocein Scarlet 8 B 

Fast Brown G Fast Brown N. 

Fast Brown 0. 
Fast Yellow Fast Yellow G. 

Fast Yellow 3 3. 

Fast Yellow 3 4. 

Fast Yellow Y. 

Imperial Scarlet, in powder, extra Imperial Scarlet 3 B. 

Safranin Safranin S P. 

Safranin A G extra. 
Safranin AGT extra. 
Safranin Cone. 
Safranin extra G. 
Safranin FF extra No. 0. 
Safranin G extra GGS. 
Safranin G 000. 
Safranin T. 

This comparison disclosed a considerable lack of conformity be- 
tween the United States food-color trade in 1907 and the circular of 
February, 1899, upon whose preparation for seven months prior to 
its date ''a great deal of thought and labor have been given to a 
thorough investigation of the whole subject of 'colors in confec- 
tionery/ in which the committee has been largely aided by the 
researches of the association's chemist and by the results of his 
analytical tests" and whose '' classifications have been carefully 
made, and are based upon the authority of the eminent chemists, 
Prof. Koenig and Prof. Weyl, upon the resolutions of the Swiss 
chemists and upon the French ordinances regarding the coloring of 
food products," and which list was expected to be ''of value to color 



FOOD-COLOR MAEKET, 1907. 



33 



dealers and chemists," and also was published to assist the confec- 
tioner in obeying ''the letter and the spirit" of the pure-candy lavv^s-. 
Under the heading ''Colors that have been shown to be harmless 
as used in the confectioner's art, harmless organic colors," this cir- 
cular enumerates 36 colors, for 4 of which there are no Green Table 
numbers. Of the 32 colors having Green Table numbers, 20, or 62.5 
per cent, were among those colors submitted. The Green Table num- 
bers of these colors, together with the number of sources from which 
they were obtained, follow: 



Green 

Table 

numbers. 

4 



9. 
13. 
55. 
65. 

85. 
103. 
105. 
107. 



Number 

of 
sources. 

. . . . 10 

5 

.... 1 

.... 6 

... 5 

... 2 

... 2 

... 6 

... 1 

... 7 



Green 

Table 

numbers. 

240 

269 

287 

427 

448 

451 

462 

512 

517 

520 



Number 

of 
sources. 

... 1 

... 1 

... 1 

... 2 

... 4 

... 5 

... 2 



Of these 20 colors 5 each came from 1 source; 5 each came from 2 
sources; 1 came from 3 sources; 1 came from 4 sources; 4 each came 
from 5 sources; 2 each came from 6 sources; 1 came from 7 sources, 
and 1 came from 10 sources; that is, only 2 were wanted by more 
than half the makers or importers, and only 4 by half the sources. 

It will be noted that this circular provides for a total of only 57 
different coal-tar colors; the number of avowed colors submitted 
reached 80, or 23 in excess of this number, and further, that out of 
the 57 colors referred to in this circular only 33 appeared among those 
colors submitted whose composition was acknowledged, so that for 
47, or 58.8 per cent of the avowed submitted colors, this circular is no 
specific guide. From the data obtainable from this circular, the 
following tabulation can be made : 

Harmfulness of submitted colors based on list in circular. 



Data. 


Total on 
market. 


Disclosed 
colors on 
United 

States 
market. 


Circular's 

corre- 
sponding 
list. 


Harmful 


13 
20 


Per cent. 
16.3 
25.4 


Per cent. 
61.9 
62.5 


Harmless 



These figures disclose a considerable and self-evident disregard of the 
request, then eight years old, as made by the National Confectioners^ 

97291°— Bull. 147—12 3 



34 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

Association of the United States, that coal-tar colors designated 
by it as '^colors that are injurious and therefore to be rejected, 
harmful organic colors" be not used in confectionery, and by implica- 
tion that they should not be used in other food products. 

In view of this disregard with respect to 13 coal-tar colors out of 
33 on the United States market in the summer of 1907, dealt with in 
this confectioners' list, the conclusion seemed justified that the action 
regarding other coal-tar colors on the United States market in the 
summer of 1907 was equally heedless or indifferent, a conclusion 
which is borne out by the material brought together under section IX. 

The necessity of adhering to some unequivocal terminology, as has 
been done in these pages by referring to the serial numbers in the 
Green Tables, appears from the following: 

Trade names are not definite with respect to the composition of 
the article sold under a given name, although tinctorially the colors 
may be substantially equivalent. In the Green Tables there are not 
less than 29 instances where the same trade name is applied to two 
or more different chemical individuals. In some cases these chemical 
individuals are fairly closely related, in others they are only remotely 
related. When the differences are greater than the presence or 
absence of a sulpho group or the use of methyl for ethyl or the reverse, 
the instances are given below: 

1. Cotton Yellow 128 Primulin-azo-m-phenylene-diamin-disiilphonicacid. 

191 Diphenylurea-disazo-bi-salicylic acid. 

2. Methyl Eosin 513 Methylated tetrabromo-fliiorescein. 

375 Dinitro dibromo fluorescein. 

3. New Yellow 88 p-sulphanilic acid azo-diphenylamin. 

91 Nitration product of diphenylamin yellow. 

4. Orange III 23 Meta-nitranilin azo-R salt. 

87 p-sulphanilic acid azo-dimethylanilin . 

5. Orange N 43 Toluidin azo-Schaffer acid. 

88 p-sulphanilic acid azo-diphenylamin. 

6. Orange R 97 o-toluidin-monosulphonic acid azo-betanaphthol. 

15 Anilin-azo-R salt. 

99 Xylidin sulphoacid-azo-betanaphthol. 

7. Toluylene Red 261 Dichloro-benzidin disazo R salt. 

580 Dimethyl diamido toluphenazin. 

The following quotation also bears on this point : 

In attempts to group the aniline colors a kind of uncertainty appears even among 
color chemists. The same trade name does not always correspond to the same prepara- 
tion. Many preparations are not chemical individuals, but mixtures of related colors. 
Many preparations are "standardized" for the trade; for example, with dextrin. On 
account of the patent laws, factory secrets surround the production of many coloring 
matters, and frequently statements are met with which are directly intended for the 
purpose of misleading competition. {Huejp'pe, Die Methoden der Bakterienforschung, 
5thed.,1891,p.l05.) 



LEGAL ENACTMENTS. 35 

V. SOME LEGAL ENACTMENTS RELATIVE TO THE USE OF 
COAL-TAR DYES. 

LIST OF THIRTEEN FOREIGN LEGAL ENACTMENTS. 

The 13 foreign legal enactments compared are as follows: 

1. The Austrian regulation of March 1, 1886, which forbids No. 
483 of the Green Tables and all anilin colors. 

2. The law of Austria of May 1, 1886, which forbids No. 1 of the 
Green Tables and all anilin colors. 

3. The Austrian regulation of September 19, 1895, in which cer- 
tain colors only are permitted, and all others are forbidden. There 
are 16 titles of permitted colors in this law, but these are in some 
cases so elastic and so indefinite as to include 47 entries in the Green 
Tables. 

4. The Austrian law of January 22, 1896, in which there are 17 
titles, but these are sufficiently elastic to allow of 22 entries in the 
Green Tables being included in them. 

5. The German law of July 5, 1887, which specifically prohibits 
only Nos. 1 and 483 of the Green Tables. The interpretation which 
seems to be generally placed upon this law is that all other Green 
Table members are permitted in Germany for use in foods. 

6. The Italian law of February 7, 1892, forbidding all colors except 
9 different titles, which, however, were elastic enough to include 32 
entries in the Green Tables. 

7. The law of Italy of February 7, 1902, which prohibits 37 entries 
in the Green Tables, and permits 11 specifically. 

8. The Italian decree of June 29, 1893, in which there were 7 
titles of permitted colors sufficiently elastic to include 34 different 
individuals. 

9. The Italian decree of March 24, 1895, forbidding four titles cov- 
ering only four entries in the Green Tables. 

10. The French police ordinance of May 21, 1885, in which 489 
entries in the Green Tables were prohibited. 

11. The French police ordinance of December 31, 1890, in which 
469 entries of the Green Tables were prohibited, and which also 
permitted under 9 titles 23 entries in the Green Tables. 

12. The Belgian law of 1891, which specifically forbids only four 
entries in the Green Tables. 

13. The law of the Canton of Tessin, dated May 18, 1897, which 
forbids only 4 specific entries in the Green Tables. 

SUMMARY OF COLORS PERMITTED BY THESE LEGAL ENACTMENTS. 

An examination of the 13 legal enactments made in Europe with 
respect to the use of coal-tar colors in food products discloses consid- 
erable difference of opinion as to the harmfulness or the harmlessness 
of even the same chemical individuals. To prepare an approximate 



36 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



and comprehensive summary of the effect of such legislation, the 
following plan has been followed : 

The provisions of a selected number of laws and regulations, 13 in 
number and dating from 1883 to 1902, were read with respect to 
permission or prohibition of the 695 chemical individuals listed in the 
Green Tables. The effect of each law upon each separate entry in 
the Green Table numbers was noted, either as permitted, forbidden, 
or noncommittal when the law was silent upon such entry; the laws 
were read with the understanding that what was not forbidden was 
permitted, and what was neither forbidden nor permitted was non- 
committal; if this were an incorrect or improper procedure the 
number of permitted colors would be reduced but not augmented. 
For the purposes of this first approximation, no attempt was made 
to segregate those specifically permitted from those permitted by 
blanket expressions or phrases. 

For the purposes of a side-by-side comparison, the term ''index 
number" was coined; this ''index number" gives in the first place the 
number of legal enactments that permit the color; in the second place 
the number of enactments that forbid it ; and in the third place the 
number of enactments that are silent or noncommittal. Thus : 283 
as an index number would mean 2 enactments permit, 8 forbid, 
and 3 are noncommittal; so that an index number with the 
highest hundreds would have the greatest number of permissions, 
and with the highest tens would have the highest number of pro- 
hibitions. With this understanding of these terms, the following 
table of so-called index or "P. F. N." numbers is offered: 

Thirteen legal enactments classified by Green Table numbers and the "F. F. N. figure,''^ 

or ' ' index number. ' ' 



Total 
number 
of Green 

Table 
entries. 


Index 
number. 


Green Table numbers. 


1 

1 

3 

217 

1 
366 

29 
3 
1 

22 
7 
2 
2 
3 
3 

n 

6 
2 
6 
6 
1 
2 


184 

274 

2,10,1 

364 

373 

382 

391 
454 
463 
472 
481 
544 
562 
571 
643 
652 
661 
670 
742 
751 
850 
931 


483. 
534. 
1-3. 
394-411, 415-426, 429-434, iS5\ 436-445, 484-492, 528-561, 564-583, 585-598, 

600, 602-649, 651-691, 693-695. 
103, 
6,7,10,11,12,14,16,19-22,35-40,42,43,45-54, 5&-64, 66-83, 89, 90, 93, 94, 9(>- 

101,104-106, 109-113, 115-145, 149, 151-156, 158, 159, 161, 162, 164-168, 

172, 197, 199-243, 245-393, 412-414, 493-511, 524-527, 650. 
446, 447, 449, 450, 453, 455, 456, 458-461, 463-476, 478, 479, 481, 482. 
428,563,599. 
692. 

5, 8, 9, 23-34, 84, 86-88, 91, 520, 523. 
95,452,454,477,513,519,522. 
562, 601. 
515,516. 
480,514,521. 
44,114,427. 

13, 15, 85, 92, 108, 14(>-148, 150, 160, 517. 
17,18,41,169,512,518. 
451,462. 

4, 55, 5n, 57, 102, 244. 
05, 107, 163, 170, 198, 448. 
457. 
157,171. 



» Italicized figures indicate colors permitted by F. I. D. 76. 



LEGAL ENACTMENTS. 37 

From the table it appears that there is no one Green Table number 
that is permitted by each and all of these 13 legal enactments, nor 
is there any one color that is prohibited by each and all of these 13 
legal enactments; and as late as 1902 there was considerable con 
fusion as to what should or should not be permitted or forbidden. 
That the European enactments were not in reaHty consistent or 
effective appears from the following: 

1. In respect to the use of coal-tar colors, the views as to their harmfulness or harm- 
lessness are very divergent, and this uncertainty is expressed in the various legislative 
enactments, (v. Raumer, Zts. Nahr. Unters. Hygiene &Waarenk., 1895, v. 9, p. 207.) 

2. After eating groats, which no doubt were free from ordinary poisons but had been 
colored with Martins Yellow, a whole family became sick. Since this coloring matter 
is not mentioned among those which, under the law of July 5, 1887, are forbidden 
for the purpose of coloring articles of food, a complaint could not be lodged. Never- 
theless, the use of Martins Yellow for the coloring of articles of food would seem to be 
dangerous, since this coloring matter exerts poisonous effects. It is a weakness in 
the law that coal-tar colors, of which new members are continuously appearing on 
the market, and whose physiological action is unknown, should be at all permitted 
for the coloring of articles of food. (Dietrich, Th., Jahresherichte der landwirihschaft- 
lichenVersuchsstation, Marburg, 1900-1901, p. 13; abst. Zts. Nahr. Genussm., 1902, v. 5, 
p. 364.) 

On account of their large number and the great diversity of opinion 
as to harmfulness of some coal-tar colors and the harmlessness of 
others therein reflected, no- attempt was made to collect all the 
legal enactments and regulations made with respect to coal-tar 
dyes. The foregoing are typical of the remainder. 

COLORS SAID TO BE PERMITTED UNDER THE GERMAN LAW 

OF 1887. 

That some of the laws did not employ specific terms but used those 
possessed of a great degree of elasticity appears from the following 
taken from Weyl's ^'Sanitary relations of the coal-tar colors," page 38, 
concerning the Chamber of Commerce and Trade of Sonneberg which 
declared on December 4, 1887, that the German law of July 5, 1887^ 
allowed the unrestricted use of — 

All blue and violet anilin (that is coal-tar) colors, all ponceaus, all orange colors, 
Methyl Green, Brilliant Green, Malachite Green, Chrysoidin, Naphthol Yellow, Martins 
Yellow, Eosin, Phloxin, Safranin, Erythrosin, Fuchsin, Phenylene Brown, and Anilin 
Black. 

This amounts to not less than 233 permitted colors, as will now be 
shown. 

Using the Green Tables as a guide it will be found that under the 
above ruling there are to-day no less than 107 blue coal-tar colors 
which could be used for food coloring. They are arranged as follows, 
showing the comments on same in the literature. 



38 COAL-TAB COLORS USED IN FOOD PRODUCTS. 

BLUE COLORS. 

Unfavorable: 478, 479, 488, 490, 572, 602, 639. (Total, 7.) 

Favorable: 477, 599, 600, 692. (Total, 4.) 

Contradictory: 287, 457, 480, 563, 601, 650, 689. (Total, 7.) 

Not reported on: 36, 83, 119, 142, 175, 189, 209, 246, 247, 254, 257, 263, 266, 288, 290, 
291, 292, 293, 294, 295, 301, 302, 310, 311, 314, 315, 316, 317, 318, 319, 323, 327, 345, 
347, 348, 351, 352, 356, 359, 364, 430, 432, 439, 440, 442, 444, 456, 473, 476, 481, 482, 
487, 492, 509, 542, 551, 556, 558, 559, 560, 562, 569, 595, 598, 608, 611, 612, 615, 618, 
619, 621, 625, 627, 628, 634, 637, 638, 640, 641, 642, 643, 652, 655, 656, 657, 664, 682, 
693, 694. (Total, 89.) 

Similarly there would be 50 violets which are classified as follows: 

VIOLET COLORS. 

Unfavorable: 620, 649. (Total, 2.) 

Favorable: 467, 593. (Total, 2.) 

Contradictory: 450, 451. (Total, 2.) 

Not reported on: 30, 34, 36, 118, 176, 179, 207, 244, 246, 248, 252, 256, 273, 320, 336, 
338, 340, 342, 343, 444, 452, 454, 455, 463, 464, 465, 466, 468, 469, 470, 471, 472, 474, 486, 
506, 507, 525, 552, 579, 581, 585, 592, 613, 625. (Total, 44.) 

Similarly there would be 18 ponceaus which are classified as follows: 

PONCEAUS. 

Unfavorable: None. 

Favorable: 169, 448. (Total, 2.) 

Contradictory: 13, 15, 55, 160, 163. (Total, 5.) 

Not reported on: 44, 56 ^ 57 i, 108, 113, 114, 146, 147, 148, 150, 165. (Total, 11.) 

Similarly there would be 35 Oranges which are classified as follows: 

ORANGES. 

Unfavorable: 2, 97. (Total, 2.) 
Favorable: 85. (Total, 1.) 

Contradictory: 14, 18, 43, 86, 87, 88, 95. (Total, 7.) 

Not reported on: 10, 23, 47, 54, 99, 100, 136, 162, 196, 217, 218, 222, 225, 235, 236, 
265, 275, 392, 406, 408, 409, 529, 531, 545, 547. (Total, 25.) 

The remaining 23 colors named are classified as follows: 

MISCELLANEOUS. 

Unfavorable: Martius Yellow (3). 2 (Total, 1.) 

Favorable: Naphthol Yellow S. (4); Eosin (512, 517, 521); Phloxin (521); Erythrosin 
(517). (Total, 6.) 

Contradictory: Brilliant Green (428); Malachite Green (427); Chrysoidin (17, 18, 41); 
Safranin (584); Fuchsin (448); Phenylene Brown (197). (Total, 8.) 

Not reported on: Methyl Green (460, 461); Eosin (514, 515); Phloxin (518); Safranin 
(583, 585); Erythrosin (516); Anilin Black (577). (Total, 9.) 

It will be noticed that names such as Eosin, Erythrosin, and Phloxin 
appear in more than one classification; thus some of each are favor- 
ably reported on and the others are not reported on at all. 

J Nos. 56 and 57 are included among the permitted colors of the Austrian law. 
2 The numbers in parentheses following the names are the Green Table numbers. 



LEGAL ENACTMENTS. 



39 



The 233 colors said by the Sonneberg Chamber of Commerce and 
Trade to be entitled to unrestricted use in food coloring under the 
German law of 1887 referred to may also be classified as follows: 

Summary of classification of colors -permitted under the German law of 1887 according to 

comments in the literature. 





Total. 


Comments in the literature. 


Class. 


Unfa- 
vorable. 


Favor- 
able. 


Contra- 
dictory. 


Not re- 
ported 
on. 




107 
50 
18 
35 
23 


7 
2 


2 

1 


4 
2 
2 

1 
5 


7 
2 
5 

7 
8 


89 


Violets 


44 




11 




25 


Miscellaneous 


9 






Total 


233 


12 


14 


29 


178 


>« 





Out of these 233 colors only 55, or about one-fourth, have been 
reported on in the hterature and the remaining three-fourths have 
not been examined at all. To the 55 examined and reported on 
there may be added 2, namely, Nos. 56 and 57, since they are included 
among the colors once permitted by law in Austria, thus making a 
total of 57 examined out of 232. Adding these two to the 14 favor- 
ably reported on makes a total of 16. It finally appears that 41 
out of 57 colors examined would in the hght of present knowledge 
be improper to be used in food and 12 at least should not be used for 
such purposes at all. 

The classification into unfavorable, favorable, contradictory, and 
not reported on is based upon the tabulation on page 63; if that is 
substantially correct the above conclusions are also true. 

The foregoing side-by-side comparison of 13 legal enactments, 
while it makes no claim to being absolutely and wholly accurate in 
all the classifications or conclusions drawn, is no doubt a fair reflec- 
tion of the condition of mind of those framing the enactments, and 
consequently of information upon which those enactments were based; 
and the conclusion would therefore seem to be justified that the fact 
that a color has been permitted or has been forbidden by any one or 
the majority of these legal enactments ought not to constitute a 
clean bill of health, nor an indictment, as the case may be. 

This side-by-side comparison must not be pushed to extremes; 
indeed the extent to which it can be employed is naturally very Hm- 
ited, and the purpose for which it was made was to reflect in a manner 
easily and comprehensively grasped the confusion and inconsistencies 
which very persistently force themselves upon the mind of a person 
reading those enactments and having in mind the chemical individ- 
uals at which they are aimed. 



40 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

The definite lesson to be learned from this side-by-side comparison 
is that these enactments in many cases employed terms so vague and . 
indefinite as to permit the use of some bad colors as well as all good 
ones, that is they were not sufficiently definite to exclude all that 
were harmful. 

DEFINITENESS AND DETAIL NECESSARY TO EFFECT QUALITY 

CONTROL. 

This apparent state of confusion in legal enactments that pre- 
ceded the summer of 1907 was a very strong factor in the formation 
of the conclusion that in order to be effective any law or regulation 
deahng with coal-tar colors for use in foods must prohibit every coal- 
tar color except certain definite specific ones. 

The Austrian laws of September 19, 1895, and of January 22, 1896, 
provided for quahty control by pubHc and other laboratories of the 
coal-tar colors put upon the market for use in foods; the results of 
such control, as reported in the Zeitschrift fiir Nahrungsmittel- 
Untersuchung, Hygiene und Waarenkunde, 1896, v. 10, p. 335, are 
as follows: 

Coloring matters of commerce are mostly mixtures of various coloring matters, a 
right which manufacturers will not part with; and further, while it is indeed possible 
to test the coloring matter in substance, it is nevertheless impossible to test it in the 
very small amounts which are used in the coloring of foodstuffs and to determine 
with certainty the identity of the color as to whether it is or not one of the permitted 
colors. 

Of 21 samples of coloring matter examined, 14 were objectionable, partly 
because of false labeling, or because they were mixtures, partly because they 
contained poisonous metals," or a forbidden coloring mJitter. Thus, a so-called ''Ever- 
green" was Naphthol Green B, a poisonous nitroso color; Malachite Green contained 
zinc; an Acid Magenta and a Rosalin contained traces of copper; Ponceau, Eosin, 
Brown, and Roccellin contained traces of tin; Orange I and Waterblue contained 
traces of tin and zinc. The last-named coloring matters were therefore not prepared 
in proper state of purity. 

The authorities in Vienna examined four and rejected two colors. {Ibid., 1898, 
p. 107.) 

The Swiss authorities exercised control over colors, after they 
reached the market, with the result that the authorities in Basle 
examined ten colors and rejected one. {Ihid., 1897, p. 292.) 

These facts, together with the knowledge derived by even the most 
superficial ocular examination of the 294 specimens received in the 
summer of 1907, played a very great part in the formation of the con- 
clusion that control of quality, in order to be even reasonably efl'ec- 
tive, must be thoroughgoing, and that colors must be excluded from 
the market until they prove themselves to be clean, rather than 
permitted promiscuously and then driven out of the market by the 
authorities if unsuitable. 

The effective quality control of food colors requires careful and 
searching examination of a kind which can not usually be obtained 



LEGAL ENACTMENTS. 41 

by the general purchasing pubUc. The quality of the food colors 
offered in the summer of 1907 varied greatly, and the substances 
contaminating them were of such indefinite and probably variable 
composition (of whose physiological action nothing definite was 
known and whose quick and certain detection in the colored food 
product would be very complicated, if not impossible) that quality 
control of greater efficiency than that exercised by those selling 
food colors in the summer of 1907 seemed necessary on the part of 
the authorities having charge of the enforcement of the food and 
drugs act. 

The points of original entry of food colors into the United States 
food-color market are relatively few, whereas the points of distribu- 
tion of food colors are very many, the former being less than 20 and 
probably fewer than 10, while the latter may number up into the 
hundreds; therefore, not only is the labor and the expense of quality 
control of food colors reduced to its probable minimum by keeping 
food colors off the market until they have shown their right to be 
so used, but also the certainty and the efficiency of quality control 
is increased to its probable maximum. 

The quality control thus suggested is similar to that exercised by 
the States of New York, Michigan, and Ohio over salt before it 
enters the market for human consumption. The method of color 
control here suggested differs only in degree, not in kind, from the 
quahty control exercised over salt by the States named. Experience 
has shown such quality control of food colors to be not only practi- 
cable but capable of realization mthout any hardship and but little, 
if any, inconvenience to those concerned. 

STATE LAWS PROHIBITING THE USE OF COLORS IN CERTAIN 

FOODS, 1909. 

The laws of the individual States of the United States have also 
restricted the use of coal-tar coloring matters in foods. These 
restrictions are directed principally against the use of color to con- 
ceal inferiority, which restriction is found in almost all the States. 

The sale of poisonous coloring matters for foods is prohibited in the 
State of New York, and in New York and North Carolina the addition 
of injurious colors to foods is prohibited. 

Minnesota and North Carolina prohibit coal-tar dyes in all foods. 

Foods and beverages are considered adulterated in North Dakota 
and Wyoming if they contain anihne dyes or other coal-tar dyes. 

Artificial coloring is prohibited in sausages by Colorado and 
Wisconsin. 

Artificial coloring, including, of course, coal-tar colors, must not be 
added to vinegar in the States of Arkansas, CaHfornia, Connecticut, 
Iowa, Minnesota, Missouri, New Jersey, New York, Pennsylvania, 
Tennessee, Wisconsin, and Wyoming. 



42 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Distilled vinegar must not contain artificial color in Ohio and 
Oklahoma, and must be free from harmful artificial coloring matter 
in Utah. 

In South Dakota oleomargarine must not be colored. 

Artificial coloring is prohibited in milk by California, Oklahoma, 
Pennsylvania, Utah, and Wisconsin and in cream by California 
Connecticut, Pennsylvania, Utah, and Wisconsin. 

Coal-tar dyes are inhibited in cakes, crackers, candy, ice cream, 
and like products by Virginia. Ice cream is considered adulterated 
in Michigan if it contains harmful colors. 

Forty-six States prohibit the use of poisonous colors in candy. 
They are as follows: Alabama, Arkansas, California, Colorado, Con- 
necticut, Delaware, District of Columbia, Florida, Georgia, Idaho, 
Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, 
Maryland, Michigan, Minnesota, Missouri, Montana, Nebraska, 
Nevada, New Hampshire, New Jersey, New York, North Carolina, 
North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Philippine 
Islands, Porto Rico, Rhode Island, South Carolina, South Dakota, 
Tennessee, Texas, Utah, Vermont, Virginia, Washington, Wisconsin, 
and Wyoming. 

VI. RECOMMENDATIONS BY ASSOCIATIONS AND INDIVIDUALS 
AS TO USE OF COAL-TAR DYES AS FOOD COLORS. 

CAZENEUVE AND LEPINE. 

Cazeneuve and Lepine {Bull, de Vacad. de medicine, April 27, 1886, 
f. 6Jf.3) says: 

We have arrived at the following conclusions: 

1. The nitro derivatives are especially poisonous (dinitronaphthol being comparable 
with picric acid), but the sulphonated product is harmless. 

2. Safranin and Methylene Blue are harmful, producing gastric intestinal dis- 
turbances, being violent poisons. 

3. The following coloring matters are tolerated by man, whether well or affected 

with Bright's disease; similarly, too, animals (dogs, guinea pigs) without any noticeable 

disturbances and at rather high doses: 

Probable Probable 

Green Table Green Table 

Nos. Nos. 



5. Ponceau R 55 

6. Orange 1 85 

7. Fuchsin S 462 



1. Fast Yellow 9 

2. Roccellin 102 

3. Bordeaux B 65 

4. Purple 106 or 107 

Among the nontoxic sulphonated colors we have been able to make out the following 
list or classification, based upon their power of producing disturbances, proceeding 
from the least inert to the most inert: 



Probable 

Green Table 

Nos. 

1. Orange I 85 

2. Bordeaux B 65 

3. Ponceau R 55 

4. Roccellin 102 



Probable 

Green Table 

Nos. 

5. Yellow NS 4 

6. Fast Yellow 9 

7. Purple 106 or 107 



EECOMMENDATIONS BY ASSOCIATIONS, ETC. 43 

The results of our experiments have led us to the following conclusions: 

1. The relative nonpoisonous nature of the azo colors used for coloring wines explains 
why this artificial coloring has not caused smy real epidemic. 

2. This artificial coloring of wines by coal-tar colors is dangerous. It opens the door 
to the employment of coloring matters of very variable and noxious properties. Thus 
Martins Yellow, which is poisonous, has been used for 10 years past to color pastry 
(3 grams per 100 kilograms) and it may be used to-morrow, perhaps, to color wines mixed 
with a red or a blue. 

3. A rigid law against the artificial coloring of wines ought to be promulgated, 
particularly if this coloration covers detestable practices most prejudicial to the public 
health. The addition of salicylic acid, glycerin, and tartaric acid, or the acidifying 
by sulphuric acid, is cloaked by the use of the coloring matter. 

Some sulphonated azo-coloring matters are sufficiently inert to enable their being 
employed as artificial color in foods, bonbons, and liquors. These colors are manu- 
factured according to simple processes which give theoretical yields and no metallic 
salt, such as mercury, tin, or arsenic participates; sulphate of soda is the only impurity. 

In view of the great extent of the use of these coloring matters, it is better to regulate 
their consumption by tolerating certain of these products rather than to interpose an 
illusory barrier to their use. Where you can not arrest a stream you can at least regu- 
late its course. 

It would be better definitely to classify these substances with respect to their noxious 
properties, tolerate some and prohibit the others, rather than to be exposed to the 
consequences of permitting manufacturers to introduce into food, without any scien- 
tific control whatever, any products whatever. 

These coloring matters should be sold in commerce under the names of harmless 
colors as determined by analysis. By chemical analysis it would be recognized as to 
whether we were dealing with one color or with a mixture of two or three colors. 

The colors most used are made up of red, yellow, and blue, which apparently imitate 
the appearance of the wines of the Midi. Thus we have recognized such coloring 
matters in Roccellin, Naphthol Yellow, and Methylene Blue. 

Sulphonated Fuchsin is very much used, combined with a yellow and a blue. This 
mixture turns green with ammonia, like the coloring matter of wine. In fact, Acid 
Fuchsin is decolorized by ammonia. The yellow and blue remain intact, and give a 
green which suggests true wine color. 

SOCIETY OF SWISS ANALYTICAL CHEMISTS. 

In 1891 the Society of Swiss Analytical Chemists recommended 
that certain coloring matters which are to be regarded as harmful 
to health should not be permitted to be used in the preparation of 
articles of food intended for sale in which artificial coloring is at all 
permitted. 

The coal-tar colors thus prohibited are identified in the following 
by their Green Table numbers, only one trade name being given: 
Picric Acid (1); Dinitrocresol (2); Martins Yellow (3); Aurantia (6); 
Orange II (86); Metanil Yellow (95); Safranin (584); Methylene 
Blue (650). {Zts. Nahr. Unters. Hygiene, 1891, v. 5, f. 293.) 

TSCHIRCH. 

In 1893 Tschirch recommended as follows: 

1. The coal-tar colors, and in a narrow sense the anilin colors, are no longer harmful 
on account of their arsenic content, since at the present time the great majority of 
them are prepared free from arsenic. 

2. Some colors have shown themselves to be harmful to the system. 



44 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

3. Coal-tar colors in general should therefore be permitted for the coloring of foods, 
but those that have been found to be harmful should be expressly and specifically 
forbidden. 

4. The amount of coloring matter which has been determined quantitatively in 
bonbons and liqueurs is so small that even the ones regarded as poisonous would not 
be able to develop their harmful effects. (Zts. Nahr. Unters. Hygiene Waarenk., 
1893, V. 7, p. 338.) 

KAYSER. 

In 1895 Kayser expressed himself as follows: 

As to the poisonous nature of organic coloring, and in respect to their composition, 
H. Erdmann (Pharm. Centralh., 1892, v. 33, p. 357) concludes that in general acid 
dyestuffs can pass as nonpoisonous; whereas in the case of basic coloring matters it 
is recommended to make a physiological examination before using them for the col- 
oring of things in daily use, especially articles of food. Whether that portion of that 
view which deals with acid dyestuffs will retain unexceptionable and positive validity 
appears doubtful. 

At the present time, speaking generally, interested manufacturers take the point 
of view that all the coloring matters which are not forbidden in the food law are to be 
regarded as permitted. Whether this point of view is free from legal objection can 
not be discussed here; that, however, it can not be accepted from a hygienic point of 
view under any circumstances whatever does not require any special proof for those 
conversant with the facts. The hygienic requirements under all circumstances 
can be summed up in the following rule: 

Every coloring matter is to be regarded in every way as suspicious, so far as its 
harmlessness is not proven by experience or by correct physiological experiments. 

No one can say in advance that among the colors which are to-day manufactured 
and used, which are as yet not called into question, there are none which possess 
distinctly poisonous properties. Correct examination of artificial coloring matters in 
this direction is, as is well known, even to the present almost wholly lacking. {Forsch- 
ungsberichte uber Lebensmittel, etc., 1895, Vol. II, p. 181.) 

WEYL. 

In 1896 Weyl expressed himself as follows: 

Since the number of the organic coloring matters already known is a very large one, 
and since their number is increasing daily, and it seems to be unlikely that each 
individual of these coloring matters will be examined as to its poisonous nature, there 
are only two ways left in which to solve the question as to the use of coloring matters 
in the manufacture of food and articles of daily use. 

One of them, and at the same time the simplest, would be to prohibit the use of all 
coloring matters for the coloring of foods, etc. This rigorous point of view will hardly 
ever be taken by legislators, because it would be tantamount to the removal of many 
marks of differentiation which have become desirable and necessary. 

The second way seems to be the much more practicable, and which Theodor Weyl 
proposed some time ago. 

It consists in permitting the use of only a definite number of coloring matters, recog- 
nized as harmless, for the coloring of articles of food, etc. \Miich coloring matters 
are to be so permitted is to be determined by the authorities having jurisdiction. 
The same authorities are also to determine the maximum amount of each coloring 
matter which can be used for any purpose. New coloring matters can be used only 
for the above-mentioned purposes when they have been recognized as nonpoisonous 
after official test. All permitted coloring matters must be also detectable, even in 
email amounts. {Handhuch der Hygiene, 1896, Vol. Ill, p. 385.) 



KECOMMENDATIOlsrS BY ASSOCIATIOITS, ETC. 45 

NATIONAL CONFECTIONERS' ASSOCIATION. 

In 1899 the National Confectioners' Association of the United 
States issued an official circular, which has been previously discussed/ 
designating certain colors as harmful, and certain others as harmless ; 
the members of each class are given in the following hst, in which 
only one trade name is given, the Green Table number appearing in 
parentheses at the end of that name. 

Harmful Organic Colors. 

Red colors: Ponceau 3RB (163); Crocein Scarlet SB (160); Cochineal Red A (106); 
Crocein Scarlet 7B (169); Crocein Scarlet extra (164); Safranin (584). 

Yellow colors: Picric Acid (1); Martius Yellow (3); Acme Yellow (84); Victoria 
Yellow (2); Orange II (86); Metanil Yellow (95); Sudan I (11); Orange IV (88). 

Green colors: Naphthol Green B (398). 

Blue colors: Methylene Blue BBG (650). 

Brown colors: Bismarck Brown (197); Vesuvin B (201); Fast Brown G Q38); Chrys- 
oidin (17, 18). 

Harmless Organic Colors. 

Bed colors: Artificial Alizarin and Purpurin (534); Eosin (512); Erythrosin (517); 
Rose Bengale (520); Phloxin (521); Ponceau 2R (55); Bordeaux B (65); Ponceau 2G 
(15); Fuchsin S (462); Archil Substitute (28); Orange I (85); Congo Red (;240); Azoru- 
bin S (103); Fast Red D (107); Fast Red (105); Ponceau 4GB (13); Fuchsin (448). 

Yellow and Orange cofors.- Naphthol Yellow S (4); Brilliant Yellow (5); Fast Yellow 
(8); Fast Yellow R (9); Azarin S (70); Orange (43). 

Green colors: Malachite Green (427); Dinitrosoresorcin (394). 

Blue colors: Indigo (689); Gentian Blue (457); Couplers Blue (600). 

Violet colors: Paris Violet (451); Wool Black (166); Azoblue (287); Mauvein (593). 

Brown colors: Chrysamin R (269). 

SCHACHERL. 

Schacherl in 1903 made the following statement: 

If coal-tar colors are to be permitted for the coloring of food, then, in my opinion, 
it is not right to limit the use of such to a few coloring matters, but groups of coloring 
matters must be permitted which are without suspicion from a sanitary standpoint, 
and which are characterized by definite reactions. Other groups, on the other hand, 
which contain harmful or merely suspicious colors, must be absolutely excluded. 
* * ^ The selection would be easily made if sufficient data were at hand with 
respect to the physiological action. Unfortunately this is lacking, a circumstance 
which need not be surprising in view of the very large number of synthetic coloring 
matters, since the Schultz-Julius tables enumerate 681 such colors. Unfortunately 
the experiments of Th. Weyl, which were planned on a large scale, have not been 
completed, and apart from isolated investigations we are limited in passing judgment 
upon the most of these colors to the proof that to date nothing with respect to harmful 
action has become known. * -5^ * Consequently it is still possible that one or the 
other coloring matter which may to-day be regarded as above suspicion, or a newly 
discovered coloring matter may possess poisonous properties; the legislators should 
under all circumstances have the power to exclude for use in foods all suspicious 
combinations, and all such coloring matters as are not easily distinguishable from them. 

I See also p. 30. 



46 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



The final recommendations of Schacherl amount to permitting — 

1. All the Azo colors, Nos. 7 to 393 of the Green Tables, except No. 86. 

2. All the Triphenylmethane colors, Nos, 427 to 492 of the Green Tables, except 
the hydroxyl derivatives, which would be Green Tables Nos. 483, 484, 485, 486. and 491. 

3. All Pyronins, Nos. 493 to 527 of the Green Tables. 

4. All Oxyketones, Nos. 537 to 570 of the Green Tables. 

5. All Indulins, Nos. 599, 601, and 603 of the Green Tables. 

6. Naphthol Yellow S, G. T. No. 4. 

7. Methylene Blue, G. T. No. 650. 

The use of all other coal-tar colors would best be forbidden, partly from hygienic 
and partly from practical considerations (rendering control more easy) , until the 
absolute harmlessness of the group in question is determined by physiological test. 
* * * It should be required of all permitted coloring matters that they shall not 
contain substances which are harmful to health, or even suspicious, either in chemical 
union or as contaminations. {Fifth International Congress of Applied Chemistry, Ber- 
lin, 1903, Vol. IV, pp. 1041-1048.) 

The exclusions recommended are all nitro-colors, except Naphthol 
Yellow S; all acridin colors and all chinolin colors; Auramin, In- 
dophenol and all nitro-colors, except Naphthol Yellow S, Schacherl 
regards as not necessary; further, he has no knowledge of the physio- 
logical action of any of the azoxy or the tliiobenzenyl colors, and 
aside from Methylene Blue, he has no knowledge of the physiological 
action of the oxazins and thiazins. 

CLASSIFICATION OF RECOMMENDATIONS IN THE LITEilATURE. 

The following table shows the groups of coal-tar colors of the 
Green Table classification and the Green Table numbers of the 
members of each of the groups, together with the favorable or unfa- 
vorable recommendations found in the literature in regard to each 
and a statement as to those regarding which no recommendations 
are made: 

Tabulation of recommendations fou7id in the literature. 



Group 
num- 
ber. 


Green 

Table 

number. 


Name of color. 


Number of individuals 
reported on — 


Total number. 


Un- 

favor- 
ably. 
(1) 


Favor- 
ably. 

(2) 


Con- 
flict- 


Re- 
ported. 

(4) 


Not re- 
ported. 

(5) 


1. 


1-6.... 

7-132 . 
133-336. . 
337-382. . 
383-393.. 
394-398. . 
399-416.. 
417-424.. 
425-426. . 
427-492.. 
493-527. . 
528-533.. 
534-570. . 
571-578. . 
579-616. . 
617-648.. 
649-657.. 
658-663. . 
664-667. . 
668-688. . 
689-695.. 


Nitro 


4 
3 
3 


2 
10 
3 



19 
7 


6 

32 
13 





2 


Monoazo . ..... 


94 


3. 


Disazo 


191 


4 


Trisazo. 


46 


5 


Tetrakisazo 










11 


6 


Nitroso 






1 

1 


1 



2 

1 


3 


7 


Slilbene 


17 


8 


Oxyketone 


8 


9 




1 
5 
2 
2 




5 
5 





8 
1 

1 

2 

1 




1 


1 
18 
8 
2 
1 
3 
7 
2 
4 
1 
1 
2 
2 


1 


10 


Triphenylmethane 


48 


11 


Xanthenes . . . 


27 


12 


Acridin 


4 


13 


Anthracene 


36 


14 


Indophenols 


2 1 


5 


15 

16 


Azlns 

Oxazins 


2 
2 
3 
1 
1 
2 



3 





1 


31 
30 


17 


Thiazins 


5 


18... 


Thiobenzen vl 


5 


19 


Quinolin 


3 


20 


Sulphids 


19 


21 


Indigos. 


5 




Total 






33 


32 


41 


106 


589 









RECOMMENDATIONS BY COLOR INDUSTRIES. 47 

CONCLUSIONS. 

Applying the Schacherl rule, '^ Other groups which contain harmful 
or merely suspicious colors must be absolutely excluded/' to this 
table and assuming that all entries in columns 1 and 3 shall be 
regarded as rendering such colors as ''harmful or merely suspicious," 
it will be found that only one group, namely the Stilbene group, 
would be permitted under that rule; further, that this rule would 
admit 17 colors, not one of which has been reported on in the litera- 
ture as to its physiological action. This state of affairs tends to em- 
phasize the difficulties in the way of any generalization which will be 
safe so far as public health is concerned and fair to those who use 
food colors for admittedly legitimate purposes and to make the 
following recommendation appears to be the only satisfactory way 
of solving the food-color problem : 

Although it would be possible to draw quite reliable conclusions as to the advisa- 
bility of employing certain colors for food products on the basis of their chemical 
constituency, the mode of their manufacture and of the ingredients used in same, 
nevertheless, I think that by far the safest way would be on the one side to force 
the dealers of colors intended for food products to sell only such colors with which 
exhaustive and careful physiological tests have been made by experienced and espe- 
cially impartial and thoroughly reliable people, thereby establishing their harmless- 
ness beyond a doubt. On the other hand, the manufacturers and canners of food 
products of any description should be forced to purchase and use only those colors 
which they are sure have been submitted to such careful tests as have been described 
and by these tests found to be harmless. (Lieher, The use of coal-tar colors in food 
products, 1904, p. 150.) 

This view is confirmed by Santori ^ {MolescJiotfs Untersuchungen, 
1895, Vol. XV, p. 67), who says: 

From all these experiments it follows that it is impossible, as some have desired to 
do, to conclude simply from the chemical composition and constitution whether any 
given coal-tar dye is poisonous or nonpoisonous. Thus Indulin belongs to the same 
group as Printing Blue and Methyl Violet to the same group as does Acid Violet; 
therefore each individual coal-tar dye must be separately examined, and it is only 
by this laborious method that the use of all really poisonous coal-tar dyes will be 
prevented. 

VII. RECOMMENDATIONS MADE BY UNITED STATES COLOR 
INDUSTRIES AND TRADES TO THE DEPARTMENT OF AGRI- 
CULTURE. 

Prior to the issuance of any regulations, the commission on rules 
and regulations for the food and drugs act, June 30, 1906, held meet- 
ings in New York City during September of that year. The steno- 
graphic reports of those meetings, and the briefs filed, in so far as they 

1 Santori examined 15 different blue and violet dyes on dogs by the mouth and hypodennically. Of 
these 15, 8 are poisonous by the mouth and 7 are nonpoisonous by the mouth. He found Indulin to be pois- 
onous and Printing Blue to be nonpoisonous; Acid Violet to be nonpoisonous and Methyl Violet to be 
poisonous. 



48 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

relate to colored food, colored food products, or material for coloring 
foods or food products, have been condensed verbatim in the following 
pages with the sole exception of omissions, as indicated ; for obvious 
reasons the names of those making the suggestions hereinafter quoted 
are not given. This review of opinions expressed and recommenda- 
tions given by the industries and trades most interested in the manu- 
facture, use, and sale of food colors and colored food products is 
believed to be fair and full with respect to each and every quotation. 
The numbers in parentheses following each quotation refer to the 
pages in the stenographic minutes of the hearing from which those 
quotations are made. 

ANTAGONISTIC TO ALL ADDED ARTIFICIAL COLOR. 

1. Our position in the coloring question is that we are opposed to all artificial coloring 
matter in food products. * * * (p. 109). 

2. Secondly, speaking first of our own business, and I believe that my view would 
hold as regards all food products, it is my opinion that all added artificial coloring 
matter in food products should be prohibited. My experience in our line of business 
demonstrates this to me beyond any question of doubt (p. 439). 

CONCERNING RESTRICTIONS AND REQUIREMENTS. 

WHAT CLASSES OP COLORS SHOULD BE PERMITTED TO BE USED. 

1. All colors, irrespective of their class, whether animal, vegetable, or synthetic, 
which have been physiologically and chemically examined, and which will neither 
retard digestion nor have special physiological effects when consumed in quantities 
corresponding to two grains per day per adult (p. 106). 

2. On the use of colors we recommend that any kind of a harmless color should be 
permitted provided it is not a color generally known to be poisonous, or generally 
found to be poisonous, or one that may be almost impossible to be produced without 
containing some poison within itself, when finished and ready for use (p. 119). 

3. Only such colors as are guaranteed to be harmless by reliable manufacturers should 
be used in the manufacture of confectionery (p. 555). 

WHY COAL-TAR COLORS SHOULD NOT BE BARRED. 

4. Coal-tar colors, as a class, should not be prohibited; but all those coal-tar colors 
generally found to be poisonous, or which are hard to produce without containing 
poisonous properties when ready for use, should be forbidden the privilege of being used 
or offered for sale for use in food (pp. 116, 117). 

5. I ought to put in a plea for the use of coal-tar colors, harmless, of course, for the 
reason that we have not as yet been able to find any vegetable coloring that is suitable 
that will give us the results that we require. Coal-tar colors, as everybody knows, 
are much stronger and are more soluble and not acted upon by acids, whereas the 
vegetable colors, with but one exception, which is a dark red, we have found great 
difficulty in making use of for bottled soda water. Almost all the vegetable colors 
either fade out or change on account of the citric acid in the syrup or food, or form in a 
little while a precipitation which renders the goods unsalable (pp. 119, 120). 

6. * * * aniline butter colorings ^ ^ * are superior to all vegetable colors 
in the following points: (1) Shade and brilliancy. (2) Strength, by which less 
foreign material is introduced into the butter. (3) Permanency when exposed to 
light and cold storage. (4) No effect on the taste or flavor. (5) A clear solution 



RECOMMENDATIONS BY COLOR INDUSTRIES. 49 

without sediment or mud which gives the butter a uniform tint without specks (pp. 
176, 177). 

7. We recommend * * * that the use of harmless coal-tar colors, such as 
chrysoidine, tropaeoline, azoflavine, rocelline, ponceau, Bordeaux, Biebrich red, 
sulphonated fuchsin and naphthol yellow S be allowed, subject to declaration on the 
label of the quality and quantity of the color used (p. 226). 

RELATION OF LABEL TO COLORED FOOD PRODUCTS. 

8. * * ^ if it seems wise in the opinion of the commission to allow certain color- 
ing matters in food products, then the names of the coloring matter ought to be stated 
on the article (p. 109). 

9. * ^ * I suggest that the use of aniline colors should be made proper if it is 
so stated on the label (p. 127). 

10. We recommend * ^ * that the use of harmless coal-tar colors * * * be 
allowed subject to declaration on the label of the quality and quantity of the color 
used (p. 226). 

LABELING OF FOOD COLORS AS DISTINGUISHED FROM COLORS FOR OTHER USES. 

11. We recommend that if by any means the Government has the power under 
the food laws to compel color manufacturers so to do, they be compelled to label all 
packages containing colors intended to be used in articles of food as colors intended 
for such purposes as distinguished from colors intended for other purposes; * * * 
(pp. 555, 555a). 

THE TEST OF A HARMLESS COLOR. 

12. A harmless color is one "which will neither retard digestion nor have special 
physiological effects when consupied in quantities corresponding to two grains per 
day per adult" (p. 106). 

QUANTITY OF COLOR TO BE CONSIDERED IN DETERMINING HARMLESSNESS. 

13. The quantity of 2 grains is mentioned here because in confectionery where 
these harmless colors are more used perhaps than in any other product, it would be 
a proportion of one part of color to 3,500 parts, representing 1 pound of color to 3,500 
pounds of confectionery, and that is why that was accepted, because that is practi- 
cally the maximum quantity used in confectionery (p. 106). 

14. In the very minute quantities in which the colors are used in carbonated bev- 
erages, it would seem a great hardship to prevent us from usiag coal-tar colors. One 
ounce of coal-tar red will color satisfactorily from 1,000 to 2,000 gallons of soda water. 
Of yellow and orange 1 ounce will color from 1,000 to 8,000 gallons. It is readily 
seen that unless the coloring used is absolutely a violent poison it can have abso- 
lutely no effect on the consumer who takes it in an 8-ounce glass, and who could 
not possibly consume half a gallon or a gallon of that product (p. 119). 

15. On this basis 1,000 pounds of butter would contain 420 grains of aniline color 
(p. 183). 

16. One ounce of color to 30 pounds colored food (p. 135). 

THE NUMBER OF DIFFERENT COAL-TAR COLORS REQUIRED. 

17. And if I were on this committee I would advocate taking out two or three 
dyestuffs which beyond any shadow of doubt are harmless, and which have been 
experimented upon, and which would be sufficient for all the purposes of the industry 
■^ * ^ none of these colors are patented, anybody can manufacture them (pp. 
147, 148). 

97291°— Bull. 147—12 4 



60 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

18. You have been told that the food commission of the State of Pennsylvania is 
going to rule that seven colors shall be allowed in the State of Pennsylvania. That 
is not enough, because it is not possible to reproduce all of the required shades with 
those colors unless you take the seven primary colors, when you can reproduce any 
colors. But it is absolutely necessary to have about three yellows to meet the require- 
ments of the trade. Some of the articles that are put out have an organic acid nature, 
and the anilines will stand that. * * * On that account the character of the 
food product must be taken into account in the use of the color, and the confectioners 
have about 30 colors that I know positively of * * * (p. 160). 

19. We recommend that * * * chrysoidine, tropaeoline, azoflavine, rocelline, 
ponceau, Bordeaux, Biebrich red, sulphonated fuchsin, naphthol yellow S be 
allowed * * * (p. 226). 

MANUFACTURING REQUIREMENTS WHICH COAL-TAR COLORS MUST FULFIL. 

20. Coal-tar colors, as everybody knows, are much stronger and are more soluble 
and are not acted on by acids. * -J*- * Almost all the vegetable colors either fade 
out or change on account of the citric acid in the syrup or food, or form in a little 
while a precipitation which renders the goods unsalable (p. 119). 

21. There are many of these colors (coal-tar colors) that will not stand the natural 
acids produced in manufacturing foods. For instance, in making confectionery, in 
boiling candy you make a certain grade of candy where the mixture is boiled to 
230°. A certain color will stand that temperature. Then you take another candy 
and that is boiled to 320° or 340° F., and the colors that will stand 230° will in many 
cases not stand the temperature of 340°, while another class of colors will stand that 
temperature. So you have got to distinguish and get a color that will stand these 
difficult requirements (pp. 159, 160). 

GUARANTEES AND GOVERNMENT CONTROL. 

22. Only such colors as are guaranteed to be harmless by reliable manufacturers 
should be used in the manufacture of confectionery (p. 555). 

23. We recommend * * * that the Government procure samples of such colors 
from time to time, wherever they have jurisdiction so to do, and if such colors be not 
legal for such purposes under the food law, that the same be prosecuted and driven 
off the market in so far as the Government has the power to do so; and if no means 
can be devised to compel such labeling of colors intended for food purposes, then 
that the Government procure such evidence as possible as to the purpose for which 
a color is intended to be used, and if such evidence shows a food purpose, that such 
color be prosecuted if illegal under the food law (pp. 555, 555 a). 

24. See page 13. 

25. The chemical test is the first, and that might throw out a color on account of 
its containing a little tin or zinc, or some substance foreign to the food product. 
Whether that is deleterious in the quantity in which it is present or not is immaterial 
(p. 160). 

26. In a brief filed the following suggestions were made: 

It must be stated that all the chemist can determine is whether or not the colors 
contain some impurities that are known to be of poisonous nature. Aniline colors are 
or can be made entirely free of such impurities, and with this fact established the task 
with the chemist is exhausted. When it comes to decide the question whether or not 
a color by itself, when free of all impurities, is injurious to health or not, then the 
chemist is not the proper authority; it is for the physiologist and for the medical pro- 
fession to pass on such questions. Chemical theories go for nothing in deciding such 
questions. It would not even do to classify colors or other substances according to 
their makeup, as it has been shown again and again that substances belonging to the 
same chemical class are entirely different in regard to the physiological conduct. 



INVESTIGATIONS ON HARMFULNESS. 51 

Reliable information on this subject can be gained only by physiological experiment, 
as we can not say definitely whether a substance, color or any other, is injurious or 
not without finding out for every substance by experiment. This has been done for a 
considerable number of aniline colors, and these experiments are the only things that 
deserve any attention. Everything else is idle talk. ^ * ^ There are a very 
large number of aniline colors that have not been treated yet, and we are safe in saying 
that among these will be also some harmless and others injurious. As they have not 
been experimentally tested, we do not know which are harmless and which are not; 
It will therefore be clear that a law forbidding the indiscriminate use of aniline color 
for the purpose of coloring articles of food is necessary and useful. 

But if the meaning of the law is to prevent only the use of injurious colors, as it 
appears to be, then the way to proceed would be very definitely outlined. Besides 
physiological colors, all such colors should be forbidden that have been found to be 
injurious and such aniline colors as have not been tested sufficiently. There will 
then be left over a number of aniline colors which have been proven by experiment 
to be entirely harmless, even if taken in large doses. 

The experimentors were quite impartial. They had no preconceived ideas, but 
started simply to find out the true state of affaks. Their reports are therefore very 
reliable, and it will not do to overlook or to ignore them. The colors that they found 
harmless can be considered perfectly safe, so much the more as the doses conveniently 
taken with food would be much smaller than the doses that have proven to be harm- 
less. These harmless aniline colors carry all the shades wanted in the food industry. 
The law should provide that one of these colors (or mixtures of these) must be used 
when a food article is being colored, because these few aniliue colors are the only 
colors that can be considered perfectly safe as far as our present knowledge goes. 
Nothing should be left to guesswork or experimenting, as is the case just now. The 
colors that are permitted should be enumerated by their scientific as well as by their 
commercial names, and only such colors should be listed as permissible for coloring 
food products as have been proven to be harmless, even in large doses. Provision 
should be made to insure the purity of the colors sold for coloring food; the manner 
of packing such colors and the labeling of same should be laid down clearly, and all 
colors now listed, aniline as well as physiological colors, should be strictly forbidden. 
If the problem is viewed without preoccupation and prejudice, the facts given above 
will speak for themselves. 

VIII. INVESTIGATIONS, OTHEE THAN ON ANIMALS, BEARING ON 
THE HARMFULNESS OF COAL-TAR COLORS. 

PFEFFER. 

Pfeffer, writing on the Absorption of Anilin Colors by Living 
Cells, summarizes his results as follows: 

The relatively little poisonous Methylene Blue does damage protoplasm in a solution 
of 0.001 per cent. 

Methyl Violet: This coloring matter is not only stored up in the juices of the cell, 
but is also able to color the living protoplasm, and care is necessary, on account of the 
poisonous nature of the Methyl Violet, to prevent damage; these cautions are based 
upon solutions of 0.0003 to 0.00001 per cent strength. 

Methyl Violet less poisonous than Cyanin. 

Bismarck Brown about as poisonous as Methylene Blue. 

Fuchsin as poisonous as Methylene Blue. 

Safi'anin as poisonous as Methylene Blue. 

Methyl Orange is poisonous only to a slight degree. 

Tropaeolin 000, Tropeeolin 00, and Rosolic Acid are not poisonous. 



52 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Methylene Green as poisonous as Methyl Violet. 

Nigrosin as poisonous as Methyl Violet. 

Eosin (Tetraiodo fluorescein) kills in 0.1 per cent solution, but lets live 24 hours in 
0.01 per cent solution, ( Untersuchungen aus dem Botanischen Institut zu Tuehingen, 
1886-88, vol. 2, pp. 179-331.) 

WINOGRADOW. 

Winogradow reports on the influence of certain coal-tar colors on 
digestion, which experiments were carried out in glass. The con- 
clusions arrived at are as follows : ^ 

The twelve colors, Safranin (584^, Azo Fuchsin G. (93), Coerulein S. (527), Jodeosin 
(516), Magdala Red (614), Benzopurpurin (277, 278, 279, 307), Ponceau 2R (55), 
Orange II (86), Phloxin RBN (?), Chrysanilin (532), Azoflavin (92), and Cerise 
(mixture of 448 and 532), even in amounts of a few milligrams, which in relation to 
the digestive fluid make up only a few tenths or hundredths of a per cent, exercise a 
strongly retarding, almost completely inhibitive, action upon the peptic digestion of 
albumen. 

The thirteen colors, Chinolin Yellow (667), Acid Green (434, 435), Azo Acid Yellow 
(92), Naphthol Yellow (4), Primulin (659), Anilin Orange (87), Metanil Yellow (95), 
Methylene Green (651), lodin Green (459), Yellow T (84), Anilin Green (?) 
Auramin O (425), and Martins Yellow (3), retard the digestive action noticeably, 
although to a slighter degree than the flrst 12 colors; in any event they are not indif- 
ferent. {Zts. Nahr. Genussm., 1903, v. 6, p. 589.) 

HEIDENHAIN. 

Heidenhain, in his book entitled ^^Ueber chemische Umsetzungen 
zwischen Eiweisskorpern und Anilinfarben" (Bonn, Germany, 1902), 
reports on the behavior of 70 different coal-tar colors, 3 intermediate 
products, and 4 raw materials toward various albuminoids such as 
serumalbumen, albumen, and casein. 

Of these 70 colors, 21 have been investigated physiologically, and 
the results embodied in this report; and of these 21, 17 were on the 
United States market as food colors and 4 were not on this market. 

Limiting the attention to the 17 that w^ere offered, 4 of them are 
among the 7 permitted colors of Food Inspection Decision 76. 

In the cases w^here albumen and casein were used, they were 
employed in 0.5, 0.1, 0.02, 0.01, and 0.005 per cent solutions, acidified 
with acetic acid; the coloring matter w^as employed in a 1 per cent 
solution in the first strength, in 0.1 per cent solution in the second 
and third strengths, and in a 0.02 per cent solution in the fourth and 
fifth strengths, and one volume of coloring-matter solution was 
brought in contact w^ith five volumes of albuminoid solution. 

The following colors precipitated the albuminoid in all the strengths. 
The numbers in parentheses mdicate the Green Table numbers; 

» It is not always possible to identify the trade names given by Winogradow with specific numbers in 
the Green Tables; the numbers in parentheses after the name indicate the number in the Green Tables 
wherever that identification could be made with any reasonable certainty; wherever two or more numbers 
appear, the context indicates that the name might apply to any one or all of them. 



INVESTIGATIONS ON HARMFULNESS. 53 

the numbers in italics are those of the permitted list of Food Inspec- 
tion Decision 76: (55) Ponceau 2 R, (65) Fast Eed B, (434) Light 
Green SF bluish, (56) Ponceau 3 K, and (106) New Coccin. 

The following precipitated in all but tlie fifth strength: (107) 
Amaranth. 

The following precipitated only the first three strengths: (14) 
Orange G and (85) Orange I. 

The following precipitated only the first two strengths: (462) Acid 
Magenta. 

For the basic colors the method of testing was different from that 
described for the acid colors and the amounts employed were not so 
definitely set forth. A 1 per cent solution of serum albuminoid was 
employed; the solution of coloring matter used varied in strength 
from 0.5 to 1 per cent (h), a ^'very dilute solution" (a) being also 
employed. The annotations given b}'^ the author (p. 1 14) are herewith 
reproduced in full : 

(17) Chrysoidin Y. (a) In a very dilute solution the yellow base is at once liber- 
ated, and when sufficient color is added albumen precipitation takes place. No color 
change on heating. (6) Turns yellow at once. Further additional color produces a 
brown and albumen precipitation. 

(201) Manchester Brown, (a) Becomes yellow at once, due to separation of the 
free base. On heating no change. (6) Becomes a discolored brown, and produces a 
nice brown albumen precipitate. 

(425) Auramin 0. (a) No change. (6) Precipitates albumen strongly. 

(427) Malachite Green. (The oxalate of the color was used.) (a) Color changes 
from a blue-green to a more pure green. (6) Cold, no precipitation of albumen; 
heated, sudden precipitation of albumen. 

(428) Brilliant Green. (A sulphate of the color was used.) (a) Becomes milky. 
(&) Immediate precipitation of albumen. 

(448) Magenta. (Acetate and nitrate were used, and in both acted the same.) (a) 
Color changes from yellowish-red to rose-red. (6) Albumen precipitation abundant, 
even in the cold. 

(451) Crystal Violet, (a) The color loses its reddish cast and changes to pure blue. 
(6) Albumen precipitated by the use of much color. 

(4) Naphthol Yellow S was tested as the free-color acid and not as the sodium or potas- 
sium salt, which is its commercial form. It precipitated the albuminoid from the 
following solutions: 1. I per cent serum albumen in water. 2. 0.5 per cent serum 
albumen in 10 per cent acetic acid. 3. Casein, 0.5 per cent in 10 per cent acetic acid. 
4, Serum albumen; 5, Casein; 6, Nuclein, all in 0.5 per cent solution in 0.2 per cent 
sodium hydroxid. 7. Nucleinic acid in 0.5 per cent water solution. 

The relationship between the amounts of color-acid and albuminoid 
solution here used does not appear definitely in the book. 

Having reference now to the Hterature and the physiological 
action, as compiled herein, it will be observed that the abihty to pre- 
cipitate albumen, or not to precipitate it, under the conditions of 
Heidenhain, appears not to have any direct connection mth the 
results obtained by actual physiological test on animals or man. 
For instance, among the "B-Ye that precipitated all five strengths of 



54 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

albumen and casein, No. 65, Fast Ked B, of the Green Tables, has 
been found to be not harmful by tests actually described; No. 56, 
Ponceau 3 R, belongs to a class of colors generically permitted by the 
law of Austria; Nos. 55, Ponceau 2 R, and 106, New Coccine, have 
been reported on both favorably and unfavorably by different experi- 
menters; No. 434, Light Green SF bluish on physiological examina- 
tion has been described as suspicious. 

From this it appears that two colors, physiologically probably 
harmless, precipitated all the five strengths of albumen, and three 
colors, which are perhaps no more than suspicious, likewise precipi- 
tated all five strengths of albumen. 

No. 107, Amaranth, which has been examined with favorable 
results by two different experimenters, precipitates four out of the 
five strengths. 

Of the two colors precipitating the first three strengths, both have 
been examined physiologically with favorable results, namely, Nos. 
14, Orange G, and 85, Orange I. 

The color which precipitated only the first two strengths, namely, 
No. 462, Acid Magenta, has likewise been examined physiologically, 
and the reports are favorable. 

Thus it would seem that there is no definite connection between the 
physiological action and the ability to precipitate albumen from 
acetic acid solution in the case of acid colors. 

In the case of basic colors the situation seems to be somewhat 
different. 

OTHER AUTHORS. 

Rosens tiehl {Fifth International Congress of Applied Chemistry, 
Vol. Ill, p. 700) states that when the color is present in an excess, 
yeast absorbs 8 per cent of Magenta (448) and 5 per cent of Malachite 
Green (427, 428). The Acridins (528-538), the Thionins (649-657), 
the Safranins (583, 584), and the Rosanilins (447-448) dye yeast the 
best; solutions containing 3 per cent by weight of the dry weight of 
the yeast are completely decolorized by such yeast and at ordinary 
temperatures. The Eosins and Phthaleins dye the 3^east only incom- 
pletely, whereas Azo dyes (7-393) (with the exception of Benzo Pur- 
purin, 277, 278, 279, 309) do not dye yeast at all. Such dyed yeast, 
however, is not dead; it has merely lost its power to cause fermenta- 
tion. The numbers in parentheses are the corresponding numbers in 
the Green Tables as nearly as they could be identified. 

Bokorny {Chem. Ztg., 1906, v. 30, p. 217) exammed Magenta (448), 
Safranin (584), Victoria Blue (487, 488 or 490), Methylene Blue (650), 
and Alizarin Blue (562 or 563) (the numbers in parentheses are the 
probable Green Table numbers) as to their effect on micro-organisms 
such as yeast cells, infusoria, and the like, and found that these dyes 



INVESTIGATIONS ON HABMFULNESS. 55 

in a concentration of 1: 100,000 killed them, whereas strychnin 
nitrate in the same concentration is substantially without effect. 
Death is caused by absorption of the dye by the albumen of the 
protoplasm. The dyes seem to be absorbed not only by living albu- 
men, but also by Hving nerve cells and fibers. Pure anihn or coal- 
tar colors, however, are not poisonous in the ordinary meaning of the 
words, that is, humans are not likely to be easily injured by them. 

Houghton (/. Amer. CJiem. Soc, 1907, v. 29, pp. 1351-1357) shows 
that Bismarck Brown (197, 201) and Crocein Scarlet (160?) hinder 
the peptic digestion of fibrin, casein, and albumen. 

Stilling (Anilinfarhstoffe als Antiseptica, 1890, v. 2, pp. 55-56) states 
that he found the animal cells to be affected by pure coal-tar colors 
in the same way that vegetable cells were affected. 

Penzoldt, based upon the experimental work of Beckh {Archiv. 
Exp. Path,. Pharmak. 1890, v. 26, p. 310), reports as follows: 

Of the 15 dyes- 
Green Table 
Name. number. 

1. Malachite Green 427 

2. Hofman's Violet (methyl variety) 450 

3. Methyl Violet 451 

4. Rose Bengal (Erythrosin) 517 

5. Phenyl Blue 480 

6. Methylene Blue. . '. 650 

7. Fuchsin 448 

8. Coralline 484 

9. Eosin 512 

10. Methyl Orange 87 

11. Vesuvin 197 

12. Tropaeolin 88 

13. Scarlet Red (?) 

14. Congo Red 240 

15. Indulin sulpho acid 601 

all of which are water soluble and when used were free from arsenic, only the first six 
in saturated solution arrested the development of Staphylococus pyogenes aureus, and 
of these six all but the Erythrosin and Methylene Blue arrested the growth of anthrax 
bacillus. 

Of these six when injected into rabbits subcutaneously the following produced no 
changes of consequence: Erythrosin (250), Phenyl Blue (100), Methylene Blue (75). 
The numbers in parentheses show the number of milligrams of dye per kilo body 
weight of the rabbits. 

Methyl Violet (50) produced only local changes, such as gangrene. 

Malachite Green (100) and Hofman's Violet (20) produced muscular paralysis, which 
in the case of Malachite Green resulted fatally on the ninth day; in the case of Hof- 
man's Violet the paralysis was complete on the tenth day. 

The remaining nine colors are apparently of no effect upon staphylococus or upon 
anthrax. 

H. W. WiUiams {A Manual of Bacteriology, 1906, p. 200), under 
'^ Disinfectants and Germicides," says: 

Aniline dyes. Many of these substances, notably pyoktanin (Methyl Violet), pos- 
sess germicidal properties. A solution of 1:5000 will kill the anthrax bacillus in two 



56 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

hours. A much stronger solution, 1:150, is required to kill the typhoid bacillus in 
the same time. Malachite Green is said to possess even greater germicidal pow<?r than 
pyoktanin. Methylene Blue also possesses considerable germicidal power. 

IX. COMPILATION UNDER THE GREEN TABLE NUMBERS OF ALL 
INFORMATION AVAILABLE AS TO THE SUITABILITY OF COAL- 
TAR COLORS FOR FOOD. 

GENERAL STATEMENTS. 

Before entering upon a detailed study of what has been pubHshed 
for and against specific coal-tar colors, it is probably well to consider, 
for whatever they may be worth, some of the general statements that 
have been made, from time to time, in the literature relative to coal- 
tar colors, considered either as a whole or as subdivisions or classes 
thereof, and their physiological action or their suitability for use in 
foods. 

1. Schultz (Die CJiemie des SteinkoJileniheers , Brunswick, 1887-1890, 
Vol. II, p. 35), after discussing the regulations of the German Empire 
in respect to food coloring, says: 

With respect to these regulations the artificial organic coloring matters can be 
regarded, in general, as harmless. For the purposes of dyeing magenta made by 
means of arsenic acid, further picric acid, and those coloring matters which occur as 
oxalates or zinc chlorid double salts, such as Methylene Blue and Bitter Almond Oil 
Green, can be used. The use of the substances named for the coloring of food products 
is, however, suspicious and should not be permitted. 

2. Stilling (Anilinfarhstoffe als Antiseptica, Strassburg, 1890, Vol. 
II, pp. 55-56) says: 

In view of the fact that the most innocent substance, such as distilled water or com- 
mon salt, when introduced in large quantities into the organism can act fatally, the 
anilin coloring matters therefore, particularly if they be free from all admixtures, such 
as arsenic, copper, and chlorid of zinc, are to be regarded as wholly nonpoisonous. 

All experience gathered since my first publication has likewise fully confirmed this 
nonpoisonous nature. 

3. Stilling {Ber. Klin. Wochensch. 1890, p. 531) also says: 

Proceeding from purely theoretical views, and based upon these botanical and 
physiological experiments, I have recommended anilin colors as antiseptics for the 
following reasons : 

1. They are to be designated as absolutely nonpoisonous. This will be confirmed 
by every chemist acquainted with the relevant details, and also from the medical side 
this has long ago been determined by Grandhomme. The publications of this author, 
who made extensive observations and experiments in the anilin factory of Meister, 
Lucius & Bruening, appeared in the beginning of the eighties, and has hardly become 
known in medical circles. However, I was first made acquainted with this by my 
colleague, Prof. Rose, in Strasburg. 

2. That it is possible to bring about death in experimental animals by introducing 
large amounts of the coloring matter into the peritoneal cavity proves nothing against 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 57 

the nonpoisonous natui'e of these substances. This action is to be regarded as a purely 
mechanical one, a view which I will thoroughly confirm in my second communication. 
With respect to the anilin colors not soluble in water, Ehrlich long before me, in his 
excellent publication on the oxygen requirements of the organism, has arrived at this 
view, and has excellently described it as merely a penetration of the organs. 

4. Lehmann (Methoden der Praktischen Hygiene, Wiesbaden, 1890, 

p. 543) says: 

The hygienic significance of coal-tar colors has heretofore been judged quite vari- 
ously. "^Tien the intensely poisonous nature of the first impure and particularly 
arsenic-containing coloring matters became known the inclination was to judge the 
coal-tar coloring matters very strictly; when it was subsequently recognized that 
the contaminations were largely the cause of the harmfulness to health, there followed 
a period in which no poisonous coal-tar coloring matter was known in any pure con- 
dition. (Eulenberg & Vohl, 1870.) More recent investigations, however, have 
disclosed a series of coal-tar coloring matters which, as a matter of fact, possess a con- 
siderable poisonous action, and already cases, although not numerous, have become 
known in which serious and even fatal poisonings by means of pure coal-tar colors 
have arisen. Alongside of this there still continue to exist the possibilities described 
by Eulenberg and Vohl (Viertel-Jahressch. fiir Gerichtliche Mediz, 1870), whereby 
harmless coloring matters become harmful; but the realization of these possi- 
bilities has become essentially more iseldom through improvements and changes in 
manufacture. 

5. Stilling (Arch. Exper, Pathol. PharmaTc., 1891, v. 28, p. 352), in 
speaking of the anilin colors as antiseptics, says: 

It is the nonpoisonous nature of these substances, their easy solubility and dif- 
fusibility, and above all their inability to coagulate albumen which lends them their 
importance, which now can be only difficultly denied. 

Note. — The work of Heidenhain abstracted in Section VIII does 
not fully bear out this article. 

6. Erdmann {Pharm. Centralh., 1892, v. 33, p. 357) says: 

The sulphonated as well as the carboxylated coal-tar dyes will not have any pro- 
nounced action on the organism. Acid dyes may therefore be regarded in general 
as nonpoisonous, whereas in the case of basic dyes a physiological examination is to be 
recommended before they are permitted to be applied to articles in daily use or 
indeed to be used in food or drink. 

Note. — Out of the 80 different dyes on the food-color market in 
the summer of 1907 whose composition was avowed, 15 were basic 
and 65 were acid. 

7. Tschirch expressed himself as follows: 

1. The coal-tar colors, and in a narrower sense the anilin colors, are no longer 
harmful on account of their arsenic content, since at the present time the great majority 
of them are prepared free from arsenic. 

2. Some colors have shown themselves to be harmful to the system. 

3. Coal-tar colors, in general, should therefore be permitted for the coloring of foods, 
but those that have been found to be harmful should be expressly and specifically 
forbidden. 



58 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

4. The amount of coloring matter which has been determined quantitatively in 
bonbons and liqueurs is so small that even the ones regarded as poisonous would not 
be able to develop their harmful effects. (Zts. Nahrs. Unters. Hygiene Waarenh., 
1893, V. 7, p. 338.) 

8. Georgievics {Lehrhuch der Farhenchemie, Leipzig, 1S95 p. 10) 
says under "Poisonous nature of the coloring matters:" 

It is a little known fact that of the very large number of organic coloring matters 
only a few have been found to be poisonous; these are Picric Acid, Victoria Orange 
(Saffron-surrogate), Aurantia, Metanil Yellow, Orange II, and Safranin. The preju- 
dice which is still quite widely accepted that most of the artificial coloring matters 
are poisonous dates from the early periods of anilin-color manufacture, at which time 
magenta and the coloring matters made from it occurred in commerce highly con- 
taminated with arsenic. At present, however, these coloring matters are prepared 
absolutely free from arsenic, and are, as such, nonpoisonous. A few coloring mat- 
ters which occur commercially as zinc chlorid double salts, such as Methylene Blue 
and Malachite Green, may be harmful in consequence of their zinc content, and 
should therefore never be employed in the coloring of food products. * * * In 
consequence of their physiological activity some coloring matters are employed as 
medicines, indeed principally Methyl Violet, Auramin and Methylene Blue. The 
first two, known as blue and yellow Pyoctanin (pus-destroying) are, owing to their 
great antiseptic action and diffusibility, valuable medicines; on account of the 
unpleasant coloring effect accompanying them they are but little used. Methyl 
Violet was first recommended as an antibacterial remedy in diseases of the eye by 
Stilling; subsequently it has been employed in other special cases; its principal 
use, however, is in surgery for the prevention of malignant proud flesh. 

The use of Auramin is entirely analogous. 

Methylene Blue (as a free base) is used principally as an analgesic (pain-relieving 
remedy) and is given internally; on account of its ability rapidly to diffuse through 
the tissues of the nervous system; it can also be introduced by injection. It is used 
as a remedy against malaria, carcinoma, Bright's disease, etc. 

The following have been tested as remedies or as antiseptics: Safranin, Lydin 
(Mauvein), Vesuvin, Anilin Blue, Carbolic Magenta, Alizarin Yellow C (Gallaceto- 
phenone) , etc. The potassium salt of Dinitro-ortho-cresol was brought into com- 
merce by the Farbenfabriken vorm. Friedr. Bayer & Co., under the name of Anti- 
nonnin, and has given excellent results as a means against formation of mold in 
cellars and against wood fungi. 

9. Weyl (HandhucJi der Hygiene, 1896, p. 378) says: 

A few organic coloring matters, but only a very few, possess poisonous properties. 
A rule by means of which the poisonous or nonpoisonous nature of organic coloring 
materials can be determined without experiment is unknown even for those coloring 
matters whose constitution has been determined and experiments on the poisonous 
nature of organic coloring matters are very few in number. 

10. Lewin {Lehrhuch der Toxicologie, 1897, p. 230) says: 

In the use of various fabrics or of foodstuffs, which are colored with anilin or 
coal-tar colors, or in commercial contact with such colors, local and general symptoms 
of poisoning, such as eczema, swelling of the face, vomiting, diarrhea, anaesthesia, 
paresis, etc., have been observed. These are generally due to the toxic nature of 
the coloring matters, frequently to harmful ingredients of the same, and hardly ever 
to poisonous mordants. Many workmen in anilin factories show permanent spots; 
for example, on the cornea and conjunctiva, head, chest, face, and neck, without 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 59 

any interference with their general condition. Local changes of more serious nature 
have more frequently been observed in the mucous membranes and on the skin. 
Thus, in one case, a camel's-hair pencil, soaked with anilin color, accidently entered 
the eye, and at first nothing was noticed but a violet blue coloration, later inflamma- 
ion and chemosis took place. I have observed local swelling and indurations of the 
skin, particularly on the cheeks, in the case of children after they had worn caps 
colored with anilin dye. 

11. Winton {Connecticut Agric. Exper. Sta. Report, 1901, p. 181) 
says: 

Although there is evidence that most of the coal-tar dyes are not injurious to some 
of the lower animals, it is not safe to assume that they are entirely harmless to human 
beings. The dog, an animal used in most of Weyl's experiments, has a proverbially 
strong stomach, and eats with no apparent discomfort many things which would 
disturb the digestion of a man. 

12. Chlopin, in his book published in 1903 (see p. 75), states as 
follows : 

{Page 114.) * * * All the dyes examined by me I divided into three categories: 
Dyes which caused striking general symptoms of poisoning and led to the death of 
the animal, or would have led to it if the experiments were not purposely discon- 
tinued, I designate by the term poisonous; dyes which induced some separate and 
temporary symptoms of disease, for instance, vomiting, diarrhea, separation of albu- 
men in the urine, the general condition remaining normal, I designate as suspicious; 
lastly, the dyes which caused no apparent disturbance during the experiments are 
designated by the term nonpoisonous. I purposely do not call the last category 
harmless, because by our experiments the question could not be decided negatively 
as to whether the nonpoisonous dyes did not cause some finer pathological changes in 
the organism and functions which could not be detected by simple observation. 

{Pages 219-221.) Thus, according to all the investigators quoted, there were found 
altogether 22 poisonous and harmful dyes, out of about 60 dyes examined; which 
makes 36.7 per cent of poisonous and harmful dyes among those examined. 

My investigations gave 30 per cent of poisonous and 40 per cent of suspicious dyes. 

The percentages above given have a fairly well established basis, since they were 
obtained by the examination of 100 dyes, which is about one-fifth of all the dyes in 
commerce. Further, considering the distribution of the poisonous and harmful dyes 
according to various chemical groups, we find that they occur in 12 of the 18 groups, 
and we can not note any regularity in this distribution; it is impossible to say that 
there is any definite connection between the fact that the dye belongs to a certain 
chemical group and its action on the animal organism. Usually among the dyes of 
one and the same group there are some harmful ones, but there are also some harmless 
ones, and the ones and the others have very similar composition. This or that action 
of the dyes on the animal organism, as we shall presently see, is determined more by 
the delicate difference in the internal structure of their molecules than by those 
differences on which is based, at the present time, the classification of the aromatic 
dyes. 

On the basis of the whole experimental material on hand — mine and that of other 
investigators — I can make only the following very few and purely empirical generaliza- 
tions: 

1. According to the shade produced, the poisonous and harmful colors are distributed 
as follows: Most of all poisonous dyes are found among the Yellows and the Oranges; 
then come the Blues, then the Browns and the Blacks; there are very few harmful 
dyes among the Violets and Greens; among the Reds was found only one suspicious 
one, and no poisonous ones. 



60 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

2, The most poisonous dyes belong to the Nitro, Azo, Tri phenyl, and Thiazin 
groups, and also to the Auramins. 

3. A whole group of poisonous and harmful dyes is formed by the new sulphid dyes 
known as Vidal's dyes. 

{Page 224.) By the facts and observations quoted above is corroborated the opinion 
that in general the coal-tar dyes, according to the composition and properties, appear 
as substances foreign to the animal organism, and may influence harmfully the vital 
functions, even in those cases when they do not possess distinctly poisonous properties. 
For this reason many hygienists make it a principle not to allow the coloring of food 
products or of beverages with coal-tar dyes, independently of the fact whether they 
prove in actual experiments on animals poisonous or not. 

We must therefore agree with M. Rudner that food of the masses require the most 
far-reaching protection, maintaining them free from foreign additions. 

13. Koenig {Die MensMichen Nahrungs- und Genussmittel, Berlin, 
1904, Vol II, p. J^62) says: 

Even though the majority of the anilin coloring matters, in view of the small 
amounts in which they are generally employed, can not be regarded as directly harm- 
ful to health, yet the objections to their use in the coloring of food products for the 
purpose of substituting or strengthening a natural color lies in the deception con- 
nected therewith ^ * *. 

14. Fraenkel {Arzueimittel-SyntJiese, Berlin, 1906, p. 570) says: 

It is clear that the coloring property of these chemical substances stands in no 
relation to their physiological actions, but, on the contrary, the physiological actions 
depend only upon the general structure of these substances, and therefore upon their 
membership in definite chemical groups. 

{Pages 574-5.) We see, even in considering this group of substances, that they do 
not possess any specific action, but they are capable of use, preferably by external 
application, as antiseptic materials, as materials which in their action stand somewhere 
between carbolic acid and corrosive sublimate, and whose coloring property, in conse- 
quence of which they were primarily selected, is directly a hindrance in this use, 
since the coloring of the bandages and the hands of the operators and the skin of the 
patients certainly can not be regarded as a pleasant occurrence; that the antiseptic 
action stands in some relationship to the properties of the substances as coloring matter 
must be positively contradicted. It depends only on the general structure of the 
substance, and does not stand in any direct relation to the chromophore and auxo- 
chrome groups of the substances, but more closely to the aromatic nucleus. Indeed, 
it may happen that an auxochrome group diminishes the antiseptic activity of such a 
substance. 

Note. — The dyes referred to belong to the Monazo, Disazo, 
Triphenyl-me thane, Xanthin, Azin, and Thiazin classes. 

{Page 92.) The investigations of Ehrlich have shown that basic dyes color the brain 
gray, and, moreover, they color nerve fiber very well, and are therefore to be regarded as 
neurotropes. The dye acids, on the other hand, do not dye nerve fiber, and in particu- 
lar the substituted sulphonic acids do not dye tissue at all. 

15. Meyer, in his paper on ''A preliminary communication on the 
toxicity of some aniline dyestuffs" (/. Amer. CJiem. Soc, 1907, v. 29, 
p. 892), says: 

{Page 893.) "A manufacturing confectioner of this city, for whom I made examina- 
tion of colors used by him, informs me that a yellow color sold as Auramin has such 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 61 

high tinctorial power that 1 ounce will color 2,000 pounds of candy to the highest yel- 
low tint required in his business. It is obvious that the toxicity of such a body would 
have to be very high to render it harmful in such use." Conclusions of this kind do 
not take into account the possible detrimental action ensuing on healthy as well as 
diseased persons from long-continued use of small quantities of foreign substances. 

{Page 909.) The same author raises objection to feeding experiments on the ground 
that substances are thereby introduced greatly in excess of the amounts generally 
found in foods and that the ill effects ' ' are liable to be due to the excess and in long- 
continued experiments due to a cumulative action of the excess. ' ' Surely if excessive 
amounts have a cumulative action, small amounts may also finally show toxic effects 
due to retention and accumulation of the poison. To declare a substance entirely 
innocuous would require evidence as to its nontoxicity both to normal and diseased 
persons after its long-continued administration in both small and large doses. The 
most extreme contingencies would have to be provided for. The above objections to 
feeding experiments are therefore not valid. It is hoped that a study of the effects 
on metabolism of some of these substances will help to further elucidate the subject. 

He summarizes the results of his physiological investigations of 
seven different coal-tar colors as follows: 

1. Several commercial organic dyestuffs (Curcumin S, Tartrazin, Naphthol Red S, 
Carmois in B, Naphthol Yellow S, Gold Orange, and Ponceau 2 R) were studied as 
to their general effects on dogs when administered ia varying amounts and during 
fairly long periods (two weeks). 

2. None of these dyestuffs under the conditions above indicated exhibited any 
marked degree of toxicity. Thejre was only one fatal result, which may have been 
due to influence independent of the action of the colorant. 

Similar quotations from the Hterature could be added to the fore- 
going, but these are beyond question sufficient to show that a wide 
divergence of opinion as to the harmless or harmful nature of the 
coal-tar colors as a class does exist among scientific men, and that all 
those above quoted agree that there are some at least of the coal-tar 
colors which even in a pure state may be harmful to human health, 
and that the question of actual harmfulness under the conditions 
of actual use in foods and the consumption of foods is regarded by 
some as being properly answered in the negative and by others as 
being properly answered in the affirmative. The question of amount 
of color employed in the food products and the amounts of such food 
normally eaten are therefore raised by some as the deciding factors. 

In this connection the following statement from page 49 of the 
arguments before the Committee on Patents in the House of Repre- 
sentatives, April 8, 15, 16, 22, 29, 1908, may be of interest: 

* * ■^ It should be remembered that after a new chemical has been discovered 
and patented it requires as many as three years of experiment before we dare offer it 
in this country as a medicine for human beings. These experiments are conducted 
abroad before we receive it here. It is first tried on animals and gradually, with great 
caution, extended to human beings in the foreign hospitals, so as to ascertain its 
physiological effects quantitatively upon the various organs, both when those organs 
are in the healthy state and when they are affected by various disorders * * ^. 



62 COAL-TAR COLOES USED IN FOOD PRODUCTS. 

A search of the Hterature herein compiled fails to disclose any such 
searching physiological examination of any of the coal-tar colors 
recommended for use by human beings in food products, as is asserted 
in the above quotation to be necessary in the case of a new chemical 
intended for use as a drug. If Fraenkel, as quoted on page 60, is 
correct in his statement that coal-tar colors act physiologically 
because they are chemicals and not because they are coloring matters, 
then coal-tar coloring matters prior to use in foods, in which they are 
used by the young and the old, the well and the sick, without restric- 
tion and without supervision, should also be thoroughly tested, and 
very few, if any, coal-tar colors seem to have been examined with 
the thoroughness set forth in the above quotation. That uniformity 
and purity of product is necessary in order to be sure that the chem- 
ical is going to act physiologically in the same way every time is 
obvious. According to Fraenkel, what is true of a chemical is just 
as true of a coal-tar color, and if uniformity of strength and cleanli- 
ness of product are desirable when a chemical is to be used as a medi- 
cine, such properties are equally desirable when a chemical is to be 
used as an ingredient in food. 

CLASSIFICATION OF OPINIONS IN LITERATURE AND IN LEGAL 
ENACTMENTS SHOWING CONDITION OF THE MARKET IN 1907. 

The literature and legal enactments hereinafter grouped under the 
relevant Green Table numbers have been classified as (1) unfavora- 
ble — i. e., only unfavorable reports found in the literature; (2) favor- 
able, and (3) contradictory reports, as each case required; so that 
under each Green Table entry there is not only the relevant literature, 
but also the character assigned to it for the purpose of coming to a 
conclusion as to the propriety of the use of such color in foods as 
based on such literature, which conclusion formed in that respect 
the basis for Food Inspection Decisions Nos. 76, 77, and 106. 

However, it does not follow that all dyes placed in the ^^ favorable" 
list are actually harmless; the investigations or opinions reported of 
each may very well be based upon insufficient data. This classifica- 
tion, therefore, is merely intended to reflect the present state of the 
literature with respect thereto, and is not necessarily final nor con- 
clusive. 

In substantially all the recorded cases the observers directly or 
indirectly assert the absence of arsenic and mineral poisons in the 
dyes subjected to physiological test, but the kind of other impurity, 
if any, is not stated. 

For the purpose of a comprehensive survey of the literature and 
legal enactments, the following tabulation is presented: 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



63 



Condition of the United States color market in the summer of 1907. 



[x=not on market. Figiires indicate number of dealers offering sampl 

groups.] 


e. Cross lines separate the several 


Green 

Table 

number. 


Unfa- 
vor- 
able. 


Favor- 
able. 


Con- 
tradic- 
tory. 


Green 

Table 

number. 


Unfa- 
vor- 
able. 


Favor- 
able. 


Con- 
tradic- 
tory. 


Green 

Table 

number. 


Unfar 
vor- 
able. 


Favor- 
able. 


Con- 
tradic- 
tory. 


1 


X 
X 
X 

X 






164 
166 
169 
188 
197 
201 
240 
269 
277 
287 


X 






521 
527 




X 

X 




2 






X 

1 


i" 

4 




3 








H 
5 


10 

X 




530 

532 


X 
X 
















2 














1 


i" 


563 








g 






5 
1 

2 
6 
2 

X 
X 

2 
1 

X 
X 

2 

X 








9 






X 




572 
574 
576 


X 
X 






11 








1 






13 










X 




14 






394 
398 




X 


2" 




15 






584 
593 
599 
600 
601 
602 
614 






1 


16 












X 
X 
X 




17 






399 




X 






18 








28 




X 


425 


3 






1 


41 






X 
X 






43 






427 
428 
433 
434 
435 
448 
450 
451 
457 
459 
462 
467 
477 
478 
479 
480 
483 
488, 490 






2 
3 






55 














65 




2 


i" 


1 


620 
639 


X 
X 






70 






78 


X 




4 


4" 

X 

5 

X 






84 




2 

8"' 

X 
X 


649 
650 
651 
654 


X 






85 




2 








2 


86 






X 
X 






87 














88 






X 

X 
X 








89 




6" 


i'" 

X 
X 


2 

X 

X 




659 


X 






92 
93 






667 


1 






94 






95 




2 






670 
675 


X 
X 






97 


1 






1 

X 






102 
103 


X 

6 

1 


5" 










X 




689 
692 








105 

106 








3 




502 
504 
512 
516 
517 
520 


2 








107 




7 




5 


Totals 
106 
250 


33 

28 


32 

2 16 






i"' 


3 


41 
2 26 


138 






X 
X 
X 


160 






5 

2 







163 















1 Italicized fibres are colors in the permitted list, Food Inspection Decision 76. 

2 On United States market in 1907. 

This table shows that of the 106 coal-tar dyes examined physiolog- 
ically only 50 were on the United States market; further, out of 33 
''unfavorable" dyes 8, or one-fourth, were on the United States 
market; out of 32 '^favorable" dyes 16, or one-half, were on the 
United States market, and finally that out of 41 ''contradictory" 
dyes 26, or very nearly two-thirds, were on the United States market 
in the summer of 1907. 

Assuming this classification to be substantially and essentially fair, 
the only Green Table numbers which are of interest for the present 
discussion are those classified under "favorable," because any color 
positively injurious or of doubtful character is considered as being 
properly excluded from use in food products. The Green numbers 
classified as "favorable" are 32 in number, as follows: If.; 5; 28; 
65; 85; 89; 92; 93; 102; 103; 105; 107; 166; 169; 240; 394; 399; 433; 
435; 462; 467; 477; 512; 517; 520; 521; 527; 576; 593; 599; 600; 



64 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



Of these 32, 16 were on the United States market in the summer 
of 1907 and their composition disclosed; they are presented in the 
following table, together with the number of dealers, out of a possible 
12, offering them for sale. 



Distribution of "favorable'' colors on the American market in 1907. 


Gr^en 

Table 

number. 


Number 
of dealers 
handling. 


Green 

Table 

number. 


Number 
of dealers 
handling. 


Green 

Table 

number. 


Number 
of dealers 
handling. 


Green 

Table 

number. 


Number 
of dealers 
handhng. 


4 
65 
85 
89 


10 
2 
2 

1 


103 
105 
107 
169 


6 
1 
7 
1 


240 
433 

435 
462 


1 
1 
4 
2 


512 
517 
520 

692 


3 
5 
2 
3 



From among these 16, six of the seven permitted colors of Food 
Inspection Decision No. 76 were selected. The process of selection 
and of elimination is described on page 166. 

CLASSIFICATION ACCORDING TO CHEMICAL COMPOSITION AND 

SUITABILITY. 

In the following table the chemical composition of the substances 
corresponding to the Green Table numbers is given, and their classi- 
fication according as the literature is regarded as being (1) unfavor- 
able, (2) favorable, or (3) contradictory in regard to the color. The 
colors are also arranged in the groups to which they belong chemically, 
so that this table shows: (1) The number of groups reported on in the 
literature, (2) the number and composition of members of each group 
so reported on, and (3) the interpretation here placed upon such 
reports in literature. This table is given in the expectation that it 
will be of use to chemists and physiologists. 



Opinions as to suitability, classified according to groups and chemical composition. 
(The chemical nomenclature is that of the Green Tables; " a " is used for alpha and " b " for beta.) 



Unfavorable. 



Favorable. 



Contradictory. 



NITBO COLORS. 

1. Symmetrical trinitrophenol. 

2. Dinitro o and p-cresol. 

3. Dinitro-a-naphthol. 

6. Hexanitro-diphenylamin. 

MONOAZO COLORS. 

78. Methyl-benzenyl-amido-thio- 

xylenol-azo-a-naphthol di- 

sulphonie acid. 
94. Benzene-azo-pyrazalone-car- 

boxy-disulphonic acid. 
97. Sulpho-o-toluene-azo-b- naph- 

thol. 



4. Dinitro-a-naphthol-b-mono- 

sulphonic acid. 

5. Dinitro-arnaphthol-a- mono- 

sulphonic acid. 



28. p-nitro-benzene-azo-a - naph- 
thylamin p-sulphonic acid. 

65. a-naphthalene-azo - b - naph- 

thol-disulphonic acid. 
85. p-sulphobenz ene-azo-a- 

naphthol. 
89. p - sulphobenzene - azo - di - 

phenylamin-su 1 p h o n i c 

acid. 
92. Diphenylamin yellow ■with 

nitro-diphenylamin. 



8. Amido - azo - benzene-di- and 

monosulphonic acid. 

9. Amido - azo - toluene - disul- 

phonic acid. 
11. Benzene-azo-b-naphthol. 

13. Benzene-azo-b- naphthol - b - 

sulphonic acid. 

14. Benzene-azo-b-naphthol di- 

sulphonic acid G. 



COMPILED DATA UNDER GEEEN TABLE NUMBEES. 65 

Opinions as to suitability, classified according to groups and chemical composition — Con. 



Unfavorable. 



Favorable. 



Contradictory. 



MONOAzo coLOBs— continued. 



93. p-sulpbobenzene-azo - dioxy- 
naphtbalene sulphonic 
acid. 

102. p-solpho-naphthalene - azo - 

b-anphthol. 

103. p-sulpbo-naphthalene-azo-a- 

naphthol-p-sulphonic acid. 
105. p-sulpho-naphthalene - azo - 

b-naphthol m o n o s u 1- 

phonic acid. 
107. p-sulpho-naphthalene - azo - 

b-naphthol-dis u 1 p h o n i c 

acid. 



DISAZO COLORS. 

164. Sulphobenzene-azo-sul p h o - 

benzene-azo-b-napbtbol - 

sulphonic acid. 
201. Hydrochlorid of toluene dis- 

azo-m-tolylene-diamin. 
277. Ditolyl-disazo-binaphtbion i c 

acid. 



166. Sulphobenzene - azo-sulpbo- 
benzene - azo - p - tolyl - b- 
' naphthylamin. 

169. Sulpbotoluene-azo-toluene- 
azo - b - napbtbol - a - sul- 
phonic acid. 

240. Diphenyl - disazo - binaph - 
thionic acid. 



NITEOSO COLORS. 

STILBENE COLORS. 

MPHENYLMETHANE COLORS. 

425. Hydrochlorid of imldo-tetra- 
methyl-diamido-diphenyl- 
methane. 

TRIPHENYLMETHANE COLORS. 

434. Dimethyl -dibenzyl-diamido- 
triphenyl-carbinol-tris u 1- 
phonic acid. 

459. Chlorid of heptamethyl-rosan- 
ilin chlorid. 



478. Triphenyl-pararosanilin di- 

and trisulphonic acid. 

479. Triphenyl-pararosanilin-t r i - 

sulphonic acid. 
488. 490. Hydrochlorid of phe- 
nyl-tetra- (penta) methyl- 
triamido-diphenyl-a-naph- 
thyl carbinol. 



394. Dinitroso-resorclnol. 



399. Azoxy-stilbene-di-sulphonic 
acid. 



433. Diethyl - dibenzy 1 - diamido- 

triphenyl carbinol-disul- 

phonic acid. 
435. Diethyl - dibenzyl - diamido- 

triphenyl-carbinol-tris u 1- 

phonic acid. 

462. Trisulphonic acid of rosani- 
lin and pararosanilin. 

477. Tripheny 1 - rosanilin - mono- 
sulphonic acid and triphe- 
nyl - pararosanilta - mono- 
sulphonic acid. 

467. Disulphonicacidofdimethyl 
dibenzyldi-ethyl triamido 
triphenyl carbinol. 



15. Benzene-azo-b-naphthol di- 

sulphonic acid R. 

16. Dimethyl-amido - azo - ben- 

zene. 

17. Hydrochlorid of dianaido-azo- 

benzene. 

18. Hydrochlorid of benzene-azo- 

m-tolylene-diamin. 

41. Hydrochlorid of toluene-azo- 
m-tolylene-diamin. 

43. Toluene-azo- b-naphthol -sul- 
phonic acid. 

55. Xylene-azo-b-naphthol-disul- 
phonic acid. 

70. Dichloro-phenol-azo-b-naph- 
thol. 

84. p-sulphobenzene-azo - resorci- 
nol. 

86. p-sulphobenzene-azo- b-naph- 

thol. 

87. p-sulphobenzene-azo-dimeth- 

ylanilin. 

88. p-siilphobenzene-azo - diphe- 

nylamin. 
95, m-sulphobenzene - azo-diphe- 

nylamin. 
106. p-sulphonaphthalene - azo-b- 
naphthol-disulphonic acid. 

138. BIsulphobenzene - disazo - a- 

naphthol. 
160. Sulphobenzene-azo-benzene - 

azo - b - naphthol - mono- 

sulphonic acid. 
163. Sulphobenzene -azo- sulpho- 

benzene-azo-b-naphthol. 
188. Disulpho-b-naphthalene-azo- 

a- naphthalene - azo - b - 

naphthol-disulphonic acid. 
197. Hydrochlorid of benzene-dis- 

azo-phenylene-diamin. 
269. Ditolyl - disazo - bi - salicylic 

acid. 
287. Ditolyl-disazo-bi-a- naphthol- 

p-sulphonic acid. 

398. Nitroso-b-naphthol-b-mono- 
sulphonic acid. 



427. Chlorid of tetra-methyl di-p- 

ami do-triphenyl-carbinol . 

428. Sulphate or chlorid of tetra- 

ethyl- diamido - triphenyl- 
carbtnol. 
448. Hydrochlorid or acetate of 
pararosanilin and rosani- 
lin. 

450. Hydrochlorids or acetates of 

mono-di or trimethyl (or 
ethyl) rosanilins and para- 
rosanilins. 

451. Hydrochlorid of penta- and 

hexamethyl-pararosanilin. 

457. Hydrochlorid, sulphate or 
acetate of triphenyl rosani- 
lin and triphenyl pararos- 
anilin. 

480. Triphenyl-rosanilin and tri- 
phenyi-para-rosanilin sul- 
phonic acids. 

483. Aurin carbinol, oxydized au- 
rin, methyl aurin, and 
pseudo rosolic acid. 



97291°— Bull. 147—12- 



66 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Opinions as to suitability, classified according to groups and chemical composition — Con. 



Unfavorable. 



Favorable. 



Contradictory. 



XANTHENE COLORS. 

502. Triethylrhodamin. 
516. Diiodo fluorescein. 



530. 
532. 



572. 



574. 



602. 
614. 



ACRIDIN COLORS. 

Hydrochlorid of diamido-phe- 
ny l-dimethy l-acridin . 

Nitrate of chrysanilin and 
homologues. 

ANTHRACENE COLORS. 



INDOPHENOL COLORS. 

Tin compound of dimethyl 
p-amido phenyl-p-oxy- 
a-naphthylamin. 

Hydrochlorids of p-pheny- 
lene-diamin-p-amidophe - 
nol and diamido-dipbeny- 
lamin. 

AZIN COLORS. 

Spirit Nigrosines. 

Amido - naphtbyl - naphtha - 
zonium chlorid and dia- 
mido napbthyl-naphtha- 
zonium chlorid. 

OXAZIN COLORS. 



620. Dimethylamido - dioxy - phe- 
nazoxonium carboxylate. 

639. Chlorid of dimethyl-amido- 
naphtho - phenoxazonium 
chlorid. 

THIAZIN COLORS. 

649. Zinc -double -chlorid of di- 
methyl - diamido-phenaz- 
thionium chlorid. 

651. Nitromethylene Blue. 

654. Chlorid of dimethyldiamido- 
toluphenazthionium. 

THIOBENZENYL COLORS. 

659. Dehydrothiotoluidin. 

QUINOLIN COLORS. 

667. Quinophthalone. 

SULPHID COLORS. 

670. Sulphohydro derivative of a 

polythiazin. 
675. Thiocatechin S (composition 

unknown). 

INDIGO COLORS. 



512. Tetrabromofluorescein. 

517. Tetraiodofluorescein. 

520. Tetraiododichlorofluoresceiu. 

521. Tetrabromotetrachloro fluor- 

escein. 
527. Sodium bisulphite com- 
pound of coerulein. 



576. New Gray (composition un- 
known). 



593. Phenyl- and tolyl-safranins. 

599. Mixtures of dianilido-amido- 

trianilido-, and tetraani- 
lido - phenyl - phenazo - 
nium chlorids. 

600. Indulins and fluorindins. 



692. Indigotin disulphonic acid. 



504. Hydrochlorid of diethyl-m- 
amido-phenol-phthalein. 



563. Dioxy-anthraquinone-b-qui- 
noiin. 



584, Diamidophenyl and tolyl- 

tolazonium chlorids. 
601. Sulphonated indulins. 



650. Chlorid of tetramethyl-di- 
amido-phenazthionium. 



089. Indigotin. 



COMPILED DATA UNDER GEEEN TABLE NUMBERS. 67 

PHYSIOLOGICAL ACTION OF COAL-TAR DYES. 
* SUMMARY OF SYMPTOMS. 

A rough summary of the symptoms noted or positively deter- 
mined to be absent, the number of the deaths produced, and the 
number of cases in which nothing abnormal was noticed may serve 
as a convenient guide in considering the detailed statements herein- 
after given relative to all the symptoms, clinical data, legislative and 
other pubhcations, or permissions. 

In the following tables are brought together most, if not all, of the 
recorded observations with respect to the humans anci other animals 
upon which the physiological action of coal-tar dyes has been studied 
as well as the results of autopsies when recorded. The columns 
headed '^ Unfavorable," ''Favorable," and '^ Contradictory" have the 
same significance as in the preceding table; itahcized numbers 
are those of the permitted colors of Food Inspection Decision No. 76. 
Asterisked numbers indicate that the dye was administered 
hypodermically. 

Experiments on Dogs. 

Table, I. — Observations on dogs. 
(Reference to Green Table numbers.) 



Symptoms. 


Unfavorable. 


Favorable. 


Contradictory. 


Deaths 


1; 2: 3; 488 or 490; 574; 639 
(2); 649. 

3; 488 or 490; 572; 574; 620; 

639; 649. 
1 




16 (2) ; 55; 70*; 86; 87; 95 (2) ; 


Autopsies 


103; 105; 399; 467; 477; 593; 
692. 


188*; 428 (2); 451 (2); 
480*; 601; 650. 
16; 55; 70*; 87 (2); 45 (2); 


Stained skin 


457; 480 (2); 601; 650. 
398. 


Stained conjunctivae 

Respiration difficulties 

Temperature normal 

Temperature high 

Temperature low 


1 




398. 


1; 3 






2; 620; 649 


467 


451; 601. 


488 or 490; 3 




457. 


488 or 490 




451. 


General depression 

Weakness 


425; 649; 675 




650. 


1; 3; 97; 649; 659 ... 




16; 483. 




1; 488 or 490; 639 - - 


17; 18; 41; 95; 138; 451; 650. 
138; 451. 


Emaciation 


488 or 490; 639 










16; 87; 428. 


Loss of appetite . . 


2; 3; 97; 425; 530; 649; 659; 

667; 670. 
649; 3 


240; 394 


16; 87; 138; 197; 428; 451; 


Aversion to food . 




483; 650. 
451. 


Colored urine 


3; 6; 78; 94; 97; 277; 425; 
434; 459; 478; 479; 502; 
516; 530; 532; 614; 620; 
651; 659; 667; 670. 


A; 5; 28; 92; 93; 103; 105; 
166; 240; 394; 399; 433; 
521; 527; 576; 599. 

240 


8; 9; 11; 13; 14; 16; 55; 84; 


Colorless urine 


86; 87; 88; 95; 138; 197; 
269; 287; 398; 428; 448; 
483; 504; 601; 650. 
287 




488 or 490; 649 


467; 477 

4; 5; 28; 166; 240; 394... 

5 


451; 480; 601. 




1; 3; 78; 94; 97; 425; 434; 

459; 479; 516; 580; 651; 

659; 667. 
78; 478 


8; 9* 11* 17, 18, or 41- 70; 


Albuminuria doubtful 


86; 88; 95; 188; 197; 269; 
287. 
138. 




670 


240 


14" 88; 269; 287. 








451 








11; 88. 


TTidnpy irritation ... . 


1 




86 


Bladder irritation 


639 




650. 


Thirst 


3 




16- 86' 87* 428 


Colored feces 


94; 425; 488 or 490; 620... 
425; 502; 614 


103; 105; 399; 477 

527 

4; 92; 103; 105; 399; 527; 
593. 


87; 88; 398; 480; 601; 650. 


Thin stool 


16" 504 


Diarrhea 


l;3; 94; 97; 479; 425; 516; 
614; 639; 649; 651; 070. 


11; 16; 84; 86; 87; 138; 269; 


Softened feces. 


428; 483; 504; 584; 650. 
95 


Bloody stool 






650. 



68 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Table I. — Observations on dogs — Continued. 



Symptoms. 


Unfavorable. 


Favorable. 


Contradictory. 


Pus in stool 






650. 


Stool desires 


502 






Vomiting 


1; 2; 3; 6; 97; 277; 425; 479; 

488 or 490; 516; 532; 574; 

614; 639; 649; 670; 675. 
675 


399; 433; 467; 576; 692... 
28 


11; 16; 86* 87' 95* 197* 269' 


Retching 


428; 448; 451; 483; 650. 
16; 86. 


Salivation 


488 or 490; 639; 649; 675 




584 


Anemia 


488 or 490; 639 






Stupor 






601 








451. 


Catarrh of eyes and nose. . 






451. 


Cramps 


1; 2 




601 




2; 675 






Tremors 






87. 


Congestion 


649 






Paralysis of limbs 

Destroys coloring matter 

of blood. 
Loss of sight 


1; 675 




16; 55; 87; 428; 450. 


1- 2 . . 










87; 601. 


Loss of hearing 






601. 








650. 











The following table discloses the results of the autopsies made and 
reported on dogs. 

Table II. — Autopsies on dogs. 



Symptoms. 


Unfavorable. 


Favorable. 


Contradictory. 


No change in internal 

organs. 
Nothing abnormal 






87. 




105; 399; 467; 477; 593 

103 


87 III; 457. 


No change except whole 
interior colored red. 

LrvsE. 

Fatty degeneration 






572; 620; 639 




601; 650. 


488 or 490 




451 (2); 480 II*; 601. 


Pale 






451 (2). 




574 






Inflamed 


649 




650. 


Blood-filled . 


574 






KIDNEYS. 

Congested 


3; 639; 649 




451 (2); 480* (II). 


Filled with decomposed 

blood corpuscles. 
Colored. 


639 




451 (2). 






480 (1); 601; 650. 


Soft 






480* II. 




488 or 490 





601. 


Blood-filled 


574 








620; 639 


. . .. 
692 




Thickened 






650. 


Inflamed 






650. 


STOMACH. 

Colored 


488 or 490 




650. 


Catarrh . 


488 or 490 




650. 




574; 649 . . 






brane. 
Punctured mucous mem- 






601. 


brane. 


639 






with colored mucous. 

LUNGS. 

Filled with blood. 


574 






Punctured 






601. 


HEART. 


574 






Paralyzed 


574 




16 (2); 87 I; 428; 87 II. 



COMPILED DATA UNDER GREEK TABLE NUMBERS. 69 

Table II. — Autopsies on dogs — Continued. 



Symptoms. 


Unfavorable. 


Favorable. 


Contradictory. 


INTESTINES. 

Colored 


488 or 490... . 




650. 


Catarrh 


488 or 490 






COLOEED. 

Brain 






650, 


Fat 






650. 


Skin 






650. 


Pleura 








Heart sac 






650. 








650. 


CEsophagus. . . 


488 or 490... 




650. 


All organs colored 






480* II. 


All organs swollen 






480* II. 


General congestion 

Peritonitis 


3(11) 










70*. 


Fat all disappeared 


639 






Flabby muscles 


639 















In this connection it may be of interest to note that out of 16 dyes 
producing death when administered through the mouth to dogs, 7 
were on the United States market in the summer of 1907. Their 
Green Table numbers are as follows, the numbers in parentheses 
indicating the number of makers or importers, out of a possible 12: 
offering them: 55 (2) ; 86 (8) ; 95 (2) ; 428 (3) ; 451 (5) ; 601 (1) ; 650 (2). 

The following table gives the Green Table numbers of coal-tar dyes 
which on administration to dogs positively did not in certain specific 
cases produce the particular disturbances recited, although the case of 
the several colors as a whole is regarded in the literature as "favor- 
able/' ''unfavorable," or ''contradictory/' as stated. 

Table III. — Observations on dogs showing definite negative results in specific cases 
grouped under the general verdict of the literature as a whole. 



Symptoms. 


Unfavorable. 


Favorable. 


Contradictory. 




614 


4; 105; 462 


95; 601. 


Diarrbea 


4/105; 462 

4; 92; 93; 105; 433; 462; 

521; 527; 576. 
4; 394 


95- 504. 




6; 97; 277; 434; 532; 614; 
651; 659. 


14; 16; 55; 84; 86; 87; 88; 




197; 398; 448; 504; 601. 


Phenol in urine... 






287. 


Loss of weight 




C92 


86. 









That is, when these dyes were tried on dogs the observers reported 
in certain specified cases, positively and definitely, the absence of any 
of the symptoms named. 

It is stated of the following colors that they produced no bad effects 
in certam specified cases: 4; 9; 65; 86; 105; 188; 197; 240; 457; 572; 
593. No bad effect except colored urine: 13, 95. No bad effect 
except albuminuria: 88,287. No bad effect except loss of weight: 
12.5 per cent (17, 18, or 41). 

It is therefore true of all of these coal-tar dyes that there are condi- 
tions under which they have been observed not to produce the bad 



70 



COAL-TAR. COLORS USED IN FOOD PRODUCTS. 



effects as above set forth; but this tabulation must not be taken to 
mean that these dyes can not, under any conditions whatever, produce 
untoward results ; the reverse is true in most cases. 

Experiments on Human Beings. 

The Green Table numbers of those colors concerning which experi- 
mental data are available on humans are as follows : 1 ; 2 ; 3 ; 4/ 6 ; 
9; (17,18,41); 55; 65; 85; 86; 95; 102; 103; 105; 106; 107; 197; 
427; 428; 448; 462; 532; 602; 650. 

The symptoms produced are classified in the following list: 



Internally administered. 



Not poisonous. 



4; 

9; 55; 65; 85; 95; 102; 

103;105;106;i07;448;462 

Poor general condition 86; 650 

Fever 2 

Loss of appetite 2 

Vomiting 3; 532; 650 

Intestinal irritant 650 

Diarrhea 532; 650 

Bladder irritant 650 

Colored urine 86; 95; 650 

Albuminuria 

Increased micturition 

Irritant 

Inflammation 532 

Dryness of throat 86 



650 
650 
532 



Bad taste in mouth 86 

Restlessness 86 

Rush of blood to head 86 

Vertigo 86; 650 

Headache 650 

Delirium 650 

Twitching of muscles 650 

Yellow coloration of skin 3 

Yellow-colored mucous membrane. 3 
Food colored with it made a family 

sick 3 

Adults withstand 1 

Children and weak adults do not 

withstand 1 

Deaths 2; 3 

13 



Autopsy 

It should be noted that of the 13 dyes here classed as not poisonous 
to humans all but No, 102 were on the United States market in the 
summer of 1907, as is shown in the following table: 

Number of dealers offering these nonpoisonous colors %n 1907. 



Green 

Table 

numbers. 


Sources 
offering 
same. 


Green 

Table 

numbers. 


Sources 
oft'ering 
same. 


Green 

Table 

numbers. 


Sources 
offering 
same. 


Green 

Table 

numbers. 


Sources 
offering 
same. 


14 
9 

55 


10 
1 
2 


65 

185 
95 


2 
2 

2 


103 

105 
106 


6 
1 
5 


107 
448 
462 


4 
2 



1 On permitted list, Food Inspection Decision 76. 
Symptoms produced by external application of certain colors {Green Table numbers). 

Dermatitis 



Eczema (17, 18, or 41); 197; 602 

Inflammation 427; 428 



Burning 2; 427; 428 

Itching 2; 6; 427; 428 

Blisters 2; 6 

Swelling 427; 428 , 

It should be noted that No. 86 has been tried on humans and has 
been found not to produce diarrhea or vomiting. 



» Hemorrhagic gastritis. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



71 



G. T. 3 has apparently killed a human at 60 mg per kilo and the 
autopsy disclosed hemorrhagic gastritis. G. T. 448 has been sug- 
gested as a possible remedy for Bright's disease. It should also be 
borne in mind that adults can stand G. T. 1 in doses of 540 to 900 mg 
daily for a long time, whereas children and weak adults stand that 
substance only poorly. 

Experiments on Small Animals. 

Eesults of experimenting on rabbits with 10 coal-tar dyes whose 
Green Table numbers are 1, 2, 86, 89, 107, 427, 448, 504, 517, and 
563 have been tabulated as follows: 



Death 

Diarrhea 

Colored urine . 
Softened feces. 



1; 2; 427*; 563* 
1 



Paralysis 427* 

Cramps 427* 

No harm produced . 89 ; 107; 448 ; 504 ; 517 



In the case of the numbers marked with an asterisk the color was 
administered hypodermically. In this connection reference should 
also be had to the paper of Penzoldt abstracted in Section VIII, 
page 55. 

The four coal-tar dyes bb, 103, 425, and 480 have been tested on 
guinea pigs and no disturbance was noticed in all, but in the case of 
103 occasional thirstiness was observed. No. 448 has been fed to 
hens without damage, and No. 2 has been recommended as an insect- 
icide, a fungicide, and a mouse poison. 

GENERAL STATEMENTS. 

The following statements may be of interest before the detailed 
compilation is read: 

1. O. Buss {Forschungsber, iiber Lebensmittel, 1896, vol. 2, fjp, 
163-197, 237), in a paper entitled ^^Contributions to the Spectrum 
Analysis of some Toxic and Pharmacognostically Important Coloring 
Matters, with Special Consideration to the Ultra-Violet,'' cites as 
poisonous the following (Green Table numbers follow in parentheses 
wherever connection could be satisfactorily established) : 



Picric Acid (1) Metanil Yellow 



Dinitro o- and p-Cresol (2) 

Martins Yellow (3) 

Aurantia (6) 

Fast Yellow (8) 

Orange II (86) 

As nonpoisonous : 

Naphthol Yellow (4) 

Eosin (512) 

Erythrosin (517) 

AnilinBlue (457) 

As doubtful: 



(95) 



Corallin (483) 

Safranin (584) 

Methylene Blue (650) 

lodin Green (459) 

Alizarin Blue S (563) 

Naphthol Green (398) 

Malachite Green (427, 428) 

Dahlia (450,451) 



Methyl Violet (451,454) | Vesuvin. 



(197,201) 



72 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



On the following Buss is noncommittal: 



Auramin (4-5) 

Biebrich Scarlet (163) 

Water blue (480) 



Magenta (448) 

Aurin i(483) 

Acid Green (435) 



Wine Green... 
Milling Red . . . 
Azo-acid Blue. 
Faetrose 



(?) 

(?) 

(36) 

(?) 



Naphthol Black of various brands, which seemed to be mixtures. 

2. It has been pointed out that the following nine colors are harm- 
less: 

Naphthol Yellow (4) 

Naphthol Brown (?) 

Chinolin Yellow (667) 

PyrotinRRO (115) 

Acid Green (434, 435) 

Most of these have not been examined experimentally, but scien- 
tific studies have been made of the poisonous quahties of Azo-Blue 
and Naphthol Yellow. (Zts. angew. Chemie, 1896, p. 24-) 

3. Chlopin in his monograph (see p. 75) says: 

On the basis of my personal experience I consider the testing of the action of coal- 
tar dyes on man not permissible, since such experiments may induce in the subjects 
of experiment more or less serious symptoms of poisoning, for which in some cases 
there are no antidotes at our disposal. To such accidents, in my opinion, only the 
experimenter himself may subject himself, because he knows what he is doing. Pre- 
liminary tests of dyes on dogs and other animals afford no guaranty of escape from dis- 
agreeable accidents which may take place in the testing of the dye on man. (Page 111.) 

These data and calculations convincingly prove how erroneous the current opinion 
is that for the coloring of food substances and beverages only exceedingly small, 
almost unweighable, quantities of dyes are used. (Page 113.) 

On page 221 et seq., the following general discussion of this subject 
is found : 

The Manner of Action op Poisonous Dyes on the Animal Organism. 

The mechanism and the chemistry of the action of the artificial dyes of the aromatic 
series on the animal organism remains to the present day, with few exceptions, 
exceedingly slightly and superficially studied. The same can be said also concern- 
ing the pathological and anatomical changes which are induced by these dyes. 

More than the others there have been studied in the toxicological respect the dyes 
belonging to the Nitro group; Picric Acid; Martius Yellow (Dinitro-naphthol potas- 
sium), and Saffron substitute (Dinitrocresol potassium.) 

According to Kobert, these dyes belong to the poisons acting on the blood. Accord- 
ing to the same authority, Methylene Blue, which belongs to the other chemical 
group of Thiazins, acts similarly. 

In the fundamental works on the sanitary investigations for the dyes, by Cazeneuve 
and Lepine, by Weyl, and by Santori, we find almost no material relating to the 
explanation of the manner of the action of the dyes. These investigators limiting 
themselves to a very cursory description of the symptoms of poisoning, and reciting 
in most general terms the results of autopsy, not even indicating the cause of death. 
Such, for instance, are the reports of autopsies made by T. Weyl and some other 
investigators, as quoted above. 



1 Apparently a purified form of Corallin. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 7S 

We may expect that more detailed investigations in this respect will be made at the 
proper time by pharmacologists, since study of the mechanism and chemistry of the 
action of the poisonous substances on the animal organism is their province; for the 
hygienist it is quite sufficient merely to establish the fact that a given substance is 
poisonous or harmful, and he need not go any further. For this reason, in those cases 
in which I desired to clear up the causes of death of the animals in my experiments, 
and to record pathological and anatomical changes (although by the terms of the regu- 
lations governing this competition, a close study of the action of the dyes, and the 
ascertainment of the mechanism and chemistry of their action was not required), I 
called in a person more competent than myself on these questions. 

Not counting the duplicates we made five autopsies all told. In all these cases death' 
resulted from paralysis of the heart. The pathological and anatomical changes in all 
cases, except one, did not present anything specific, and finally reduced themselves to 
a feebly expressed turbid swelling of the heart and of the liver, a rush of blood to the 
stomach, and a congestion of the internal organs. 

The exception was the autopsy of a dog, which died from Methyl Orange; this dog 
died with the symptoms of paralysis of a cerebro-spinal nature. This experiment was 
made twice, and the autopsies of both animals showed hypersemia in the lowest part 
of the spinal column, on the border of the anterior and the lateral columns. 

As to the symptoms of poisoning not resulting in acute death, here most frequently 
was observed vomiting, diarrhea, and albumen in the urine, showing disturbance of 
the functions of the digestive tract, and an affection of the kidneys. 

A highly typical picture of poisoning is presented by the sulphid Vidal dyes. They 
cause rapid, almost instantaneous, deafening of the animal, whereupon the animal falls 
on one side in convulsions and lies, not moving its body, but convulsively and rapidly 
twitching its anterior limbs during several minutes. The tongue hangs out of the 
mouth, a strong secretion of saliva is noted, then vomiting begins, and the dog gradu- 
ally begins to revive; with difficulty he arises on his front feet and sits down, not being 
able yet to stand on his posterior extremity, which is in a state of paresis. After a few 
hours the dog becomes normal. The symptoms of poisoning, just described, are exceed- 
ingly similar to the supposed "apoplectic form" of poisoning by hydrogen sulphid, 
which had been studied on animals by K. Lehmann, and which was observed in per- 
sons who inhaled air containing a few per cent of this gas. Air containing 0.1 to 0.3 
per cent of hydrogen sulphid kills cats and dogs in 10 minutes. 

In our experiments in which were introduced substances containing sodium sulphid, 
the poisoning must have been caused by hydrogen sulphid which was liberated from 
the dye by the acid of the gastric juice, and which could cause poisoning also through 
the stomach and through the respiratory apparatus. 

Fortunately Vidal dyes, owing to their repulsive odor, will scarcely find a wide 
application in coloring food and beverages. 

Some Reflections Regarding Further Investigations op Dyes from a Sanitary 

Standpoint. 

The present investigation, as well as all the investigations of the action of dyes on 
animals by previous investigators, had for its object the solution of the question in 
what number there exists among the dyes of the aromatic series dyes which possess 
poisonous, or more or less pronounced harmful properties (answering essentially the 
sanitary toxicological question). From the practical point of view such investigations 
presented and do present the most important interest, inasmuch as they afford a possi- 
bility of protecting the public from the use of obviously poisonous and harmful sub- 
stances, but by such investigations questions of exceedingly sanitary importance are 
not answered, namely: 

1. Ought we to consider as quite harmless those dyes which do not induce pro- 
nounced symptoms of poisoning and which are designated herein by the term non- 
poisonous? 



74 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

2. Is the usual answer which is given to the hygienist by the defenders of the unre- 
stricted use of the coal-tar dyes for coloring food products and beverages, namely, that 
in practice the dyes are introduced into the human organism in so small quantities 
that their properties can be neglected, justified? 

To both questions, besides the facts and considerations which I gave above in my 
investigations, we may reply experimentally in two ways: 

(a) By prolonged investigations continued over a period of years of the action of 
very minute quantities on the animal organism, which has so far, owing to the incon- 
veniences of such long experiments, not been done by anybody; and 

(6) By investigation of the action of small doses of dye on some physiological func- 
tions, and first of all on the activity of the digestive organs, which is first of all dis- 
turbed upon the introduction of dyes into foods and beverages. The solution of the 
last question can be best promoted, in my opinion, by experiments made on dogs and 
by exploratory examination of the body according to the method of Prof. Pawlow. 
Unfortunately, experiments such as these, owing to the diflaculty of the Heidenhain- 
Pawlow operation, are inaccessible to the majority of investigators. 

As a very useful substitute of such investigations may serve observations on the 
action of dyes on the activity of the digestive juices outside the body of animals. 

On my proposition Dr. A. E. Winogradow began in my laboratory experiments on 
the action of small doses of dyes of the aromatic series on the digestion in vitro. Dr. 
Winogradow so far examined 25 coal-tar dyes in this respect according to the method of 
Metta and convincingly proved that in insignificant doses coal-tar dyes (from one-half 
to 4 milligrams) entirely stopped the digestion of albumen by artificial gastric juice. 
It was found that the capacity to depress the digestion is possessed not only by poison- 
ous dyes, but also by dyes which proved in my experiments on animals nonpoisonous. 

It is quite possible, therefore, that an admixture of coal-tar dyes will exert an unfa- 
vorable influence on the digestion and assimilation of food prepared from products col- 
ored by them. Experimental proof of the last supposition can be given only by experi- 
ments" on the influence of dyes on the metabolism of substances in animals and man. 

COMPLETE DETAILED STATEMENT OF ALL COMBINED DATA. 
ABBREVIATIONS OF AUTHORITIES CITED. 

The data hereinafter given is brought together as nearly as pos- 
sible under the Green Table numbers to which it is pertinent. It is 
beheved that the literature has been quite thoroughly searched, and 
that nothing of substantial importance has escaped recording in this 
compilation; certainly whatever may have escaped can hardly serve 
to change the general conclusion to which this compilation leads. 

In order to avoid repetition in the following tabulation, '^Weyl" 
is to be understood as referring to the book entitled '^The Coal Tar 
Colors, with Especial Keference to their Injurious Qualities, etc.," by 
Theodor Weyl, translated by Leffmann and published in Philadel- 
phia, Pa., in 1892. 

'^Lieber" refers to the book entitled '^Tlie Use of Coal Tar Colors 
in Food Products," by Hugo Lieber, pubhshed in New York in 1904. 

'^Fraenkel" refers to the book entitled '^Arzneimittel Synthese," 
by Dr. Sigmund Fraenkel, pubhshed in Berlin in 1906. 

'^Confectioners List" refers to the Official Circular from the Exec- 
utive Committee of the National Confectioners^ Association of the 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 75 

United States entitled '^Colors in Confectionery" and reprinted, in 
part, in the book entitled ''Food Inspection and Analysis," by Albert 
E. Leach, pubhshed in New York in 1906, pages 630-634. 

''Resolutions of Swiss Analytical Chemists" refers to these reso- 
lutions as pubhshed in Zeitschrift fiir Nahrungsmittel Untersuchung 
und Hygiene, 1891, page 293. 

"Schacherl" refers to Schacherl's publication entitled "Die Zulaes- 
sigkeit Kuenstlicher Farbstoffe zum Farben von Lebensmitteln," 
published in Vol. Ill, pages 1041-1048, of the Report of the Fifth 
International Congress of Apphed Chemistry held in Berlin June 2 
to 8, 1903. 

"Chlopin" refers to Chlopin's monograph pubhshed in Russian 
and entitled "Coal Tar Dyes. Classification, properties, and action 
of artificial dyes on the animal organism, etc.," pubhshed at Dorp at 
in 1903, or to the abstract of Chlopin's paper printed at page 169-172 
of Vol. IV of the Report of the Fifth International Congress of Ap- 
plied Chemistry held in Berhn, 1903. 

"Canton of Tessin" refers to the pubhcations of the Tessin regula- 
tions pubhshed in 1897 in Zeitschrift fiir Untersuchung der Nahrungs 
und Genussmittel, page 414. 

Whenever possible the doses administered have been given in mil- 
hgrams per kilo and grains per 100 pounds of body weight of animal. 
In the case of the tabulations taken from Chlopin's monograph this 
was not done; but in order to render such comparative data easily 
available factors have been placed at the head of each tabulation; 
for example, under G. T. 6 (1 gram = 106 mg = 74.2 grains), which 
means that each gram administered amounts to 106 mg per kilo or 
74.2 grains per 100 pounds of body weight of animal; by multiplying 
the doses given by either of the factors the corresponding compara- 
tive information is obtained. 

In addition to the 106 Green Table numbers that have been 
examined physiologically, there are reported the results of the phys- 
iological examination of 8 coal-tar colors not in the Green Tables, of 
which 3 are said to be nonpoisonous, 3 are called poisonous, 1 is 
called harmful, and the last is said to be "not quite harmless." 
These 8 dyes are not included in this compilation. 

TABULATION BY GREEN TABLE NUMBERS OF PHYSIOLOGICAL AND 

OTHER DATA. 

G. T. 1. 

Trade names. — Picric acid; carbazotic acid. 
Scientific name. — Symmetrical trinitrophenol. 
Discovered. — 1771. 
Shade. — ^Yellow. Not offered. 



*76 COAL-TAR COLOES USED IN FOOD PRODUCTS. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

2. Weyl {p. 30): ''The injurious character of picric acid has long been known." 

3. "In Germany its employment for coloring food is forbidden by the imperial enact- 

ment of 1888, on account of its poisonous character." (pp. 68-71.) 

4. "The foregoing statements show that while the acid must be considered poisonous, 

its injurious character is far less than has generally been assumed, nevertheless, 
the legal prohibition of its use as a coloring matter for food or drink is just." 

iv- n.) 

5. "Erb gave a rabbit weighing 1,700 grams, 0.06 gram of potassium picrate (24.5 

grains per 100 pounds) daily for 90 days; slight loss of weight and occasional 
diarrhea were noted, but nothing more serious." (p. 69.) 

6. A rabbit weighing 2,065 grams died at the end of 19 days, after having taken 2.52 

grams of the substance, or 854 grains per 100 pounds body weight; number of 
doses not stated, (p. 69.) 

7. Weyl's experiment on a dog, weight not given: April 21-26, 0.24 gram (3.7 grains) 

sodium picrate daily; April 28-May 9, 0.36 gram (5.5 grains) daily; total, 5.76 
grams (8.9 grains) sodium picrate; no serious disturbance; May 13, 1.2 grams 
(18^ grains) sodium picrate at one dose; weakness marked, diarrhea and dyspnea 
next day; May 14, 0.6 gram (9J grains) caused vomiting; evening of same day, 
0.36 gram (5,6 grains) given; May 15, animal lively; 0.24 gram (3.7 grains) 
again given, and on evening of same day 0.72 gram (11.2 grains); May 16, 
marked weakness of animal, and 0.16 gram (2.5 grains) given, causing vomiting; 
May 17, 0.17 gram (2.6 grains) given; May 18 and 19, animal definitely recovered, 
and aside from strong yellow tinge of the conjunctiva and skin, no abnormal 
conditions manifest. Animal died May 20 after receiving 1.32 grams (20.4 
' grains) potassium picrate. Weyl concludes, therefore, that dogs are resistant 
to this substance, notwithstanding the prostration and the blood disorganiza- 
tion. 

8. Weyl summarizes the effect on humans from therapeutic and poisoning cases to 

the effect that daily doses of from 0.54 to 0.90 gram (8.3 to 13.8 grains) of potas- 
sium picrate are easily borne by healthy adults for a considerable time; children 
and weak adults bear picric acid badly, (p. 70.) 

9. "Picric acid * * ^ is poisonous * * *." (p. 96.) 

10. Fraenkel {p. 572): "On the other hand, this substance is not usable for internal 

administration on account of its decomposing the red blood corpuscles, and of 
its energetic cramp production, as well as on account of its distiirbance of the 
kidneys, and the ultimate paralysis of the respiratory centers; nevertheless, 
picric acid is not to be considered a violent poison * * *." 

11. ScHACHERL {p. 1044): "Picric acid * * * (is), according to numerous state- 

ments in the literature, poisonous even in small doses, and (is) therefore un- 
qualifiedly to be declared as unpermissible." 

12. LiEBER (p. 16), where it is stated to be forbidden by the German law, and is also 

otherwise substantially the same as Weyl above quoted. 

13. Resolutions of the Society of Swiss Analytical Chemists, September, 1891: "The 

following are to be regarded as coloring matters harmful to health: * * * 
picric acid * * ^." 

14. Prohibited by the Belgian law of June 17, 1891. 

15. Lewin {Lehrbuch der Toxihologie, 1897, p. 232): "Picric acid is poisonous. Rab- 

bits can stand daily 10 milligrams of a green containing picric acid, but not 20 
milligrams. Their death is accompanied by paralysis." 

16. Buss lists it as poisonous. 



COMPILED DATA UNDER GEEEN TABLE NUMBERS. 77 

G. T. 2. 

Trade names. — ^Victoria Yellow; Victoria Orange; Golden Yellow; 
Saffron Substitute; Anilin Orange; Di-nitro-Cresol. 
Scientific name. — Di-nitro-o-and-p-cresol. 
Shade. — Yellow. Not offered. 
Discovered. — 1869. 
Used for coloring butter, liqueurs, etc. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Prohibited by Confectioners' List. 

2. Fraenkel (p. 572): *'0n the other hand dinitro-cresol is much more intensely 

poisonous (than picric acid), which is probably caused by its greater solubility 
in water." 

3. ScHACHERL (p. 1044): * * * Dinitro-cresol [is], according to numerous state- 

ments in the literature, poisonous even in small doses, and [is] therefore unquali- 
fiedly to be declared as unpermissible." 

4. Resolutions of the Society of Swiss Analytical Chemists, September, 1891: ''The 

following are to be regarded as coloring matters harmful to health * * * 
Dinitro-cresol ^ * *." 

5. Forbidden by the Canton of Tessin. 

6. Weyl (p. SI): "I have shown the same (poisonous nature) for Dinitro-cresol (Saf- 

fron Substitute). (See Zts. angew. Chem., 1888, No. 12, for confirmation of my 
results by Gerlach.) " 

7. "The reverse is the case with the poisonous dinitro-cresol (Saffron Substitute). " 

(p. 55.) 

8. Weyl describes experiments with this compound, (pp. 71-85.) 

9. Fourteen rabbits were experimented on, of which 13 died. Amounts administered 

in the fatal cases per 100 pounds body weight were {p. 74): 
Grains. Grains. 

189 175 

175 168 

175 175 

175 168 

175 168 

175 175 

175 
Of 12 experiments on dogs, 5 receiving the color by the mouth and 7 hypoder- 
mically, 3 cases resulted fatally; the fatal case by the mouth requiring 38^ grains 
per 100 pounds body weight; the 2 fatal cases hypodermically represented 11 and 
20 grains per 100 pounds body weight, respectively, although 140, 38.5, 31.6, and 
35 grains per 100 pounds body weight by the mouth were borne without fatal 
effect; and 24|, 11.9, 9.8, and 4.9 grains per 100 pounds body weight, hypo- 
dermically, were also borne without fatal effect (p. 75). 

10. Weyl (p. 56): "* * * Dinitro-cresol * * * are [is] poisonous; * * *" 

11. Prohibited by the Belgian law of June 17, 1891. 

12. {Zts. Nahr. Genussm., 1892, p. 353): Recommended as an insecticide, 1500 being 

sufficient for all ordinary purposes. One milligram is sufficient to kill a mouse; 
2 milligrams recommended for killing mice. 

13. Weyl (Handbuch der Hygiene): For humans, the fatal dose, when administered by 

the stomach, appears to be 60 milligrams per kilo body weight, or 43 grains per 
100 pounds. 



78 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

14. "The president of the Council of Oppeln forbids on April 19, 1899, the use of Saf- 

fron Surrogate for coloring food products." 

15. Lewin (Lehrbuch der Toxikologie, 1897, p. 232): ''Saffron Surrogate * * *, 

which is used for coloring foodstuffs, is poisonous. It appears to attack the 
coloring matter of the blood, and produces, in the case of dogs, vomiting, cramps, 
and convulsions. * * * Feathers colored with Saffron Surrogate cause 
burning and itching, and finally blisters on the hands of the women working 
with them; the faces were also similarly affected, and this was accompanied by 
loss of appetite and fever." 

16. Buss lists it as poisonous. 

G. T. 3. 

Trade names. — Martius Yellow; Naphthol Yellow; Naphthylene Yel- 
low; Naphthylamin Yellow; Manchester Yellow; Golden Yellow; Saf- 
fron Yellow; Jaune d'Or; Jaune Naphthol. 

Scientific name. — Dinitro-alpha-naphthol. 

Discovered. — 1864. 

Shade. — Yellow. Not offered. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

2. Weyl(p. ^:?): "Cazeneuve and Lepine pointed out the poisonous nature of 

Martius Yellow * * *." 

3. " This body (Chamber of Commerce at Sonneberg) recommends for the prepara- 

tion of children's toys three colors, the poisonous character of which I can 
demonstrate. These are Martius Yellow ^ * *." {jp. 34.) 

4. "For instance, for preliminary researches, dogs and rabbits have value for 

chemical reasons. The conclusions derived from such experiments must be 
accepted with great deliberation, since it happens that rabbits will bear without 
injury doses which will seriously, nay, even fatally, act upon the dog, as I 
have already shown to be the case with Martius Yellow." (p. 56.) 

5. Where two experiments by Cazeneuve and Lepine are referred to, in which 

diarrhea, vomiting, and albuminuria were produced by this substance, 
(pp. 85-89.) 

6. Weyl's own experiments on 4 dogs showed weakness, vomiting, diarrhea, and 

albuminuria resulting from the use of this color; the amounts of color admin- 
istered per kilogram of body weight were 73, 17.5, 17.5, and 11.3 milligrams, 
which amount to 51, 12, 12, and 8 grains, respectively, per 100 pounds of 
body weight, (p. 87.) 

7. "Martius Yellow, therefore, belongs to the injurious colors. As a coloring matter 

for food and drink its use should be wholly prohibited." (p. 89.) 

8. " * * * and Martius Yellow are poisonous; * * *." (p. 96.) 

9. Lewin (Lehrbuch der Toxikologie, 1897, p. 231): "Like Saffron Surrogate, it is 

poisonous. In an experiment on myself, using large doses, I noticed among 
others the general yellow coloration of the skin. In a poisoning resulting 
fatally after 5 hours with Martius Yellow, vomiting, yellow coloration of the 
skin and mucous membranes were observed; whereas the autopsy revealed, 
among other things, hemorrhagic gastritis. (Jacobson, Hosp. Tid., 1893, p. 
765.)" 



COMPILED DATA UNDER GEEEN TABLE NUMBEES. 79 

10. " Such small amounts as are used for the coloring of pastry are said to be non- 

poisonous. {Vitalil boll, chim.farm., 1893, p. 738.)" {p. 231.) 

11. Cazeneuve and Lepine (Compt. rend., 1885, v. 101, pp. 1167-1169) say: I. "A 

dog received 71 milligrams per kilogram of body weight, or 50 grains per 100 
pounds daily. On the second day diarrhea and vomiting ensued; loss of 
appetite except for milk. Thereafter it experienced difficulties in breathing; 
suffered albuminuria; its urine was colored; it died on the sixth day. The 
autopsy disclosed considerable congestion. II. A dog weighing 22 kilos 
received 400 milligrams (19 milligrams per kilo or 13 grains per 100 pounds); 
this caused a yellow vomit; next day it received 500 milligrams (27 milligrams 
per kilo or 17 grains per 100 pounds), which caused violent diarrhea, fever, 
thirst, disLQclination for all food. The animal was killed; the autopsy showed 
badly congested kidneys." 

12. Prohibited by the Belgian law of June 17, 1891. 

13. ScHACHERL (p. 1044)' "* * '^ Martius Yellow * * * [is], according to 

numerous statements in the literature, poisonous even in small doses, and [is] 
therefore unqualifiedly to be declared as unpermissible." 

14. Prohibited by law in Italy. (See Lieber, p. 24-) 

15. Fraenkel {p. 572)'. "This substance also shows poisonous properties, although 

it is less poisonous than dinitro-cresol." 

16. Resolutions of the Society of Swiss Analytical Chemists, September, 1891: ''The 

following are to be regarded as coloring matters harmful to health * * ^ 
Martius Yellow * * *." 

17. Forbidden by the Canton of Tessin. 

18. Dietrich {Zts. Nahr. Genussm., 1902, v. 5, p. 364)' "A lot of groats, after eating 

which a family became sick, was found to be free from ordinary poisons, but 
had been colored with Martius Yellow." 

19. Buss lists it as poisonous. 

DOUBTFUL. 

1. Winogradow {Zts. Nahrs. Genussm., 1903, v. 6, p. 589) says it noticeably retards 
digestive action; is not indifferent. 

G. T. 4. 

Trade names. — Sulphur Yellow; Sulphonaphthol Acid Yellow; 
Succinic; SoKd Yellow; Saffron Yellow; Jaune Acide C; Jaune Acide; 
Fast Yellow; Citronin; Anilin Yellow; Acid Yellow S. 

Names under wMch it was offered on the United States marlcet as a 
food color in i 507.— Naphthol YeUow SLOZ; Naphthol Yellow S; 
Naphthol Yellow; Naphthol Yellow L; Yellow F Y; Lemon Yellow. 

Scientific name. — Dinitro-alpha-naphthol-beta-monosulphonic acid. 

Discovered and patented. — 1879. 

Slwbde. — Yellow. Offered by 10 out of 12 sources. 

favorable. 

1. Permitted by Confectioners' List. 

2. Cazeneuve and Lepine {Compt. rend., 1885, v. 101, pp. 1167-1169): "A dog 

received each day for 5 days 32 milligrams per kilogram of body weight, or 
23 grains per 100 pounds; for the 10 days next succeeding it received foiu" times 
that amount, that is, 133 milligrams per kilogram of body weight, or 93 grains 



80 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

2. Cazeneuve and Lepine (Compt. rend., 1885, v. 101, pp. 1167-1169) — Continued. 

per 100 pounds; for the 10 days next succeeding it received daily twice the last 
amount, or 266 milligrams per kilogram of body weight, that is, 186 grains per 
100 pounds. It received altogether in the 25 days 62^ grams, or 964 grains. 
There was no vomiting, no diarrhea, and no albumen in the urine at any 
time." 

3. Weyl (p. 31): '^ "^ * * not poisonous to human beings and dogs: Naphthol 

Yellows. * * *." 

Weyl describes his own experiments on 3 dogs, giving them, respectively, 
417, 34, and 100 milligrams per kilo body weight, or per 100 pounds 292, 24, 
and 70 grains, respectively. Whether the color was administered by the mouth, 
or injected subcutaneously, all bodily functions appeared to remain normal, 
and it was only in the case of repeated doses of 417 milligrams per kilogram 
of body weight, or 292 grains per 100 pounds, that albuminuria appeared. 
(pp. 89-92.) 

4. "Only the sulphonated colors Naphthol Yellow * * * are harmless and appli- 

cable to the coloring of food and drink." {p. 96.) 

5. Permitted by the laws of Austria. 

6. Permitted by the law of Italy. 

7. Permitted by the law of France. 

8. ScHACHERL (p. :?(9-^^): <'* * * Naphthol Yellow S * * * possesses no poi- 

sonous properties." 

9. Fraenkel {p. 572): "Naphthol Yellow S is an entirely nonpoisonous substance." 

10. Meyer (/. Amer. CJiem. Soc. 1907, v. 29, p. 900): One hundred milligrams per 

kilogram of body weight for the initial administration, and subsequent admin- 
istrations increased geometrically. After the second administration intermit- 
tent diarrhea resulted, emphasized by increased amounts with no albumin or 
sugar in the urine; continued for 14 administrations; so that in 14 administra- 
tions 147.58 grams of color had been given; the initial dose is 70 grains per 100 
pounds of body weight, and the average daily dose of the total administered 
is 394 grains per 100 pounds of body weight. Urine only slightly yellow col- 
ored after small doses, but red after larger doses. 

11. Libber (p. 14S): A dog received 36 milligrams per kilogram of body weight, or 

25.2 grains per 100 pounds once a day seven times every other day; during the 
whole period the dog was apparently in good condition with no bad effects 
from the color. 

12. Buss lists it as nonpoisonous. 

13. Cazeneuve and Lepine (Compt. rend., 1885, v. 101, pp. 1167-1169): Three 

chronic invalids received daily from 2 to 4 grams of the dye in cochets; except 
slight colic and diarrhea nothing abnormal. 

DOUBTFUL. 

1. Lewin (Lehrhuch der Toxikologie, 1897, p. 232): "Acid Yellow S is said to be able 

to produce dermatitis on frequent contact therewith." 

2. WiNOGRADOw (Zts. Nahr. Genussm., 1903, v. 6, p. 589) says it noticeably retards 

digestive action; is not indifferent, 

G. T. 5. 

Trade name. — Brilliant Yellow; Naphthol Yellow S or RS. 
Scientificname. — Dinitro-alpha-naphthol-alpha-monosulphonicacid. 
Discovered and patented. — 1884. 
SMde, — Yellow. Not offered. 



COMPILED DATA UNDER GEEEN TABLE NUMBEES. 



81 



FAVORABLE . 

1. Permitted by Confectioners' List. 

2. Weyl {pp. 92-94): Describes experiments on 2 dogs, in which the initial dose 

was 532 milligrams by the mouth, and 17 milligrams hypodermically, per kilo- 
gram of body weight, respectively, 372 and 12 grains per 100 pounds of body 
weight; in both cases the urine was colored, in the second case traces of albu- 
minuria resulted. In the first case the albuminuria was doubtful. 



3. "Brilliant Yellow is not poisonous, even in large doses, when administered by the 

stomach * * -^ the albuminuria was very slight, (p. 94-) 

4. "Only the sulphonated colors ^ ^ ^ Brilliant Yellow, are harmless, and 

applicable to the coloring of food and drink. " (p. 96.) 



* ^ * Brilliant Yellow * * 



possesses no 



5. SCHACHERL (p. 1044)'- 

poisonous properties. " 

6. Fraenkel (p. 572): "For the same reason * * * Brilliant Yellow * * * 

is without effect. " 

G. T. 6. 

Tradenames. — ^Aurantia; Nitrodiphenylamin; Imperial Yellow; 
Kaiser Yellow. 

Scientific name. — ^Hexanitro-diphenylamin. 

Discovered. — 1873. 

Shade. — Yellow. Not offered. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Weyl(p. P6): " ^ * •* Aurantia suspicious. " 

2. ScHACHERL(p. iO-^): " * * * Aurautia [is] accordiug to uumerous Statements 

in the literature poisonous even in small doses, and [is] therefore imqualifiedly 
to be declared as unpermissible. " 

3. Chlopin {p. 116) as results of his experiments considers it injurious. The experi- 

mental data are as follows: 

Experimental data by Chlopin. 
[1 gram=106 mg=74.2 grains.] 



Date. Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Mar. 12 
13 


Grams. 
1 
2 
3 

3 
3 
3 
3 


Kilos. 
9.4 


cc. 
450 
425 
400 

390 
410 
400 


Before experiment urine and dog normal. 


14 




Repeated vomiting; urine dark brown, acid; no albumen; dog 

eats. 
No vomiting; urine almost black; acid; no albumen. 


15 




18 




No vomiting; urine dark brown, acid; no albumen 


19 






20 




No vomiting; urine almost black, acid; no albumen. 


21 




425 


Same; urine chocolate brown, acid; no albumen; general condi- 


22-26 




9.3 


tion normal. 
Gradually color of urine becomes normal; in every other respect 
dog is weU. 








Total. 


18 



97291°— Bull. 147—12 6 



82 



COAL-TAE COLORS USED IN FOOD PRODUCTS. 



4. Fraenkel (p. 573): "The coloring matter called Aurantia, which is a salt of 

hexanitro-diphenylamin, appears to be poisonous on account of the nitro groups, 
which is on the other hand denied by a few observers. " 

5. Resolutions of the Swiss Analytical Chemists, September, 1891: "The following are 

to be regarded as coloring matters harmful to health * * * Aurantia 



6. Forbidden by the Canton of Tessiu. 

7. Lewin {Lehrbuch der Toxikologie, 1897, p. 232): "Aurantia has a poisonous action. 

After wearing gloves for 8 hours made with so-called dogskin, which were col- 
ored with Aurantia, a man suffered confluent blisters, accompanied by itching. 
The workmen with this material get blisters on the face and on the hands. 
Perspiration increases the tendency to such blisters. " 

8. Buss lists it as poisonous. 

G. T. 8. 

Trade names. — ^Acid Yellow; Fast Yellow G; Acid Yellow G; Fast 
Yellow; Fast Yellow extra; Jaune Acide; New Yellow L. 

Names under which it was offered on the United States marlcet as a 
food color in 1907.— Fsist Yellow Y; Fast Yellow G; Acid Yellow G 
pat.; Fast Yellow 053. 

Scientific name. — Amidoazobenzene-disulphonate with some sodium 
amidoazobenzene-monosulphonate. 

Discovered. — 1878. 

Shade. — Yellow. Offered by 5 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Cazeneuve and Lepine (Bull, de Vacad. de med., April 27, 1886, p. 643), where 

it is classified among the "nontoxic" colors. 

3. Fraenkel (p. 575), where it is stated to be nonpoisonous. 

4. Permitted by the law of Austria. 



unfavorable. 

Weyl {p. 115) : "Poisonous to human beings. (?) " 

Chlopin {p. 151) considers that the work of others makes this a suspicious color. 
His own experimental data are as follows: 

Experimental data by Chlopin. 

G. T. 8 and 9. 
[1 gram=152 mg=106 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Mar. 11-13 


Grams. 


Kilos. 


cc. 
310 


Dog normal; color urine normal; acid; no albumen. 


14 


1 


G.6 


Do. 


15 




Do. 


16 









Urine greenish brown; reddens with H2S04 and HCl; no 


17 






305 
380 
320 
280 
292 


albumen. 
Color same; traces of albumen. 


18 






Color less intense; trace of albumen. 


19 
20 


3 


G.4 


Do. 
Urine greenish brown; albumen gone; dog is lively. 
Everything normal. 


21 




0.5 






Total 


4 





Conclusion: "Suspicious. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 83 

3. Buss {Forschungsber. iXher Lebensmittel, 1896, Vol. Ill, p. 173): Is regarded as 

poisonous. 

4. KoBERT {Lehrhuch der Intoxicationen, 1893, p. 335): Listed as poisonous. 

5. Lewin {Lehrhuch der Toxihologie, 1897, p. 231) says "produces eczema," and 

dies Deutsche Med. Wochenschr., 1891, p. 45. 

G. T. 9. 

Trade names. — Fast Yellow R; Fast Yellow; Yellow W. 
Name under which it was offered on the United States marlcet as a 
food color in 1907,—Fa,st Yellow 034. 

Scientific name. — Sodium salt of amidoazotoluene-disulphonic acid. 

Discovered and patented. — 1878. 

Shade. — Yellow. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 31): " * * * not poisonous to human beings and dogs * * ^ 

Solid Yellow." 

3. Cazeneuve and Lepine {Compt. rend., 1885, v. 101, pp. 1167-1169): A. A dog 

received 42 milligrams per kilogram of body weight, or 29 grains per 100 pounds, 
for 5 days; thereupon received four times that amount for 5 days, or 168 milli- 
grams per kilogram body weight, or 117 grains per 100 pounds; for the 10 days 
next succeeding it received daily twice the last dose, or 336 milligrams per 
kilogram of body weight, that is, 235 grains per 100 pounds; it then received 
in 1 day 20 times the original dose, or 840 milligrams per kilogram body 
weight, that is, 596 grains per 100 pounds, and during the entire period nothing 
abnormal was noticed. B. Three chronic invalids received from 2 to 4 grains 
of the dye daily; except colic without diarrhea nothing abnormal. They con- 
cluded that this dye is no more harmful than Naphthol Yellow S (G. T. 4). 

4. Cazeneuve and Lepine (Bull, de Vacad. de med., 1886, p. 643): Tolerated by 

man, well or sick. 

UNFAVORABLE. 

1. Weyl (p. 115): "Poisonous to human beings. (?)" 

2. Chlopin (p. 151): Where he considers that the work of others makes this a sus- 

picious color. For his experimental data thereon see table under G. T. 8; 
Chlopin's chemical description of the dye used applies to both G. T. 8 and 9. 

3. KoBERT Lehrhuch der Intoxicationen, 1893, p. 336): Listed as poisonous. 

G. T. 11. 

Trade names. — Sudan I; Carminaph. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Oil Orange 7078; Cerasin Orange I. 
Scientific name. — Benzene-azo-betanaphthol. 
Discovered. — 1883 . 
Shade. — Orange Yellow. Offered by 2 out of 12 sources. 

FAVORABLE. 

1. Weyl {p. 115): " Nonpoisonous -=^ * * Soudan I * * *." 

2. *' Other Azo-colors, * * * for instance Soudan I * * * are entirely non- 

poisonous." {p. 148.) 



84 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

2. Weyl {p. 119): Dog received 18 grams in 6 doses in 17 days, and remained under 

observation 5 days longer; 4 doses of 168 milligrams per kilogram body weight 
(118 grains per 100 pounds) and 2 doses of 420 milligrams per kilogram body 
weight (294 grains per 100 pounds) produced colored urine, phenol in urine, 
vomiting and distinct albuminuria beginning with the third dose. From the 
foregoing Weyl concludes as follows: "The color in the doses administered is 
not entirely harmless, since a limited albuminuria seems to be brought about." 

3. Fraenkel (p. 576): " It is not wholly harmless, since this coloring matter seems 

to produce a slight albuminuria." 

G. T. 13. 

Trade names. — Ponceau 4 GB; Crocein Orange; Brilliant Orange; 
Orange G E X. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Crocein Orange 10234; Crocein Orange; Crocein 
Orange G; Ponceau 4 GB. 

Scientific name. — Anilin-azo-betanaphthol-monosulphonic acid. 

Discovered. — 1878. 

Shade. — Orange Yellow. Offered by 6 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. :?i5) : "Nonpoisonous * * * Ponceau 4 G B * * *." 

3. Experiment on dog in doses of 161 milligrams per kilogram body weight; that is, 

113 grains per 100 pounds body weight, apparently produced no disturbance 
aside from coloring of the urine, (p. 124.) 

4. Weyl (p. 148): "Other Azo-colors * * * for instance * * * New Coc- 

cin * * * are entirely nonpoisonous." 

5. Weyl's conclusion reads as follows: "This color can be regarded as nonpoisonous." 

6. Fraenkel {p. 577): "Ponceau 4GB can be regarded as nonpoisonous." 

UNFAVORABLE. 

1. Excluded by law of Austria. 

G. T. 14. 

Trade names. — Orange G; Orange G G. 

Names under which it was offered on the United States market as a 
food color in 1907. — Orange G G crystals; Orange G. 

Scientific name. — Anilin-azo-betanaphthol-disulphonic acid G. 

Discovered and patented. — 1878. 

Shade. — Orange Yellow. Offered by 2 out of 12 sources. 



COMPILED DATA UNDER GEEEN TABLE NUMBEES. 



85 



FAVORABLE. 

1. Chlopin examined this color, and his experimental data are as follows: 
Experimental data hy Chlopin. 
No. 1 (p. ISS). 
[1 gram=73 mg=51 grains.] 



Date. 


Dose. 


Weight. 


24-hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 4 


Grams. 

1 


Kilos. 
13.7 


cc. 
525 
600 
990 
550 
680 
730 
75. 


Nothing abnormal; no albumen. 

Urine light chocolate brown, acid; no albumen. 


6 


2 




Urine clear, yellow, blackish sheen; no albumen. 


7 




Urine clear, dark brown; no albumen; faintly alkaline. 


8 






Do. 


9 






Nothing abnormal. 
Do. 


10 














Total . 


3 





No. 2 (p. 12It). 
[1 gram=119 mg=103 grains.] 



1901. 
Nov. 8 
12 
13-14 

15 
16 
17 
18 
20 
21 

Total . 





8.4 


315 


3 




370 


3 
3 
3 
3 






250 
320 
210 
225 
295 
















15 



Nothing abnormal; no albumen. 

Do. 
Urine orange in color, acid, no albumen; in other respects nothing 
abnormal. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 



Conclusion : Nonpoisonous . 
1. Excluded by Austrian law. 



UNFAVORABLE. 



G. T. 15, 



Trade names. — Ponceau 2 G; Orange R. 

Scientific name. — Sodium salt of benzene-azo-beta-naphthol-disul- 
phonic acid R. 
SJiade. — Bright Red. Not offered. 



FAVORABLE. 

1. Permitted by Confectioners' List. 

UNFAVORABLE. 



1. Excluded under Austrian law. 

2. Excluded under Swiss laws. 



G. T. 16, 



Tradenames. — Butter Yellow; Oil Yellow. 
Scientific name. — Dimethyl-amido-azo-benzene. 
Discovered. — 1875. 
Shade. — Yellow. Not offered. 



86 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



FAVORABLE, 

1. Weyl (p. <?Jf): ''Butter Yellow produces no disturbance in rabbits." 

UNFAVORABLE. 

1. Chlopin {p. 138): Where as a result of his own experiments he considers it poi- 
sonous. His experimental data are as follows: 

Experimental data by Chlopin. 

No. 1. 

[1 gram=159 rag=lll grains.] 



Date. 


Dose. 


V^eight. 


General condition of animal and urine. 


1902. 
May 6 

7-8 


Grams. 
3 


Kilos. 
6.3 


Before experiment urine normal; after a few hours vomiting; urine not 

collected. 
No vomiting; eats poorly; more tired than usual. 
Dog gradually becomes normal. 
Vomiting; loss appetite. 


9-15 






16 


3 




17 




Repeated vomiting. 


18 






Vomiting continues. i 









No. 2. 
[1 gram=96 mg=67 grains.] 



1903. 
Feb. 5 



23 


10.4 











1903. 
Feb. 8 
9 

10 
11 

12 

13 
11-16 

17 
18 
19 



22 6 

3 2 ....:.... 
2 

5. 7 



Before experiment dog quite normal; acid; no albumen. 

Vomiting during night; dog does not eat, but drinks; urine more yellow 

than normal; acid; no albumen; in the evening the dog walke'd and 

drank water. 
Died during the night; thin excreta in kennel; autopsy showed paralysis 

of heart as eausmg death. 



No. 3. 
[1 gram=167 mg=117 grains.] 



Five hours after administration vomiting and involuntary thin feces. 
Dog does not eat; drinks much; weak; urine dark yellow; no vomiting. 

Do. 
Dog lies in cage; moves slowly when allowed out of cage; in the evening 

retching. 
Dog is still weak, but general condition somewhat better; urine strikingly 

colored; acid; no albumen. 
Began to eat; no albumen. 
General condition tmprovuig and almost normal; lassitude continues 

more than usual; urine normal color; acid; no albumen. 
In the evening repeated vomiting; loss of apetite. 
No vomiting; in the evening bothersome; does not eat. 
Stools normal; striking disturbance of movements; paralysis of legs; must 

spread hind legs to stand; when pushed not only falls, but turns on his 

back; sight and hearing are normal; dog died at night. 



This dog ran away. 



2 Gruebler's make. 



Berlin make. 



G. T. 17, 18, 41. 

17. Tradenames. — Chrysoidin Y; Chrysoidin crystals. 
Name under which it was offered on the United States marlcet as a 
food color in 1907. — Chrysoidin Y. 

Scientific name. — Anilin-azo-meta-phenylene-diamin. 
Discovered. — 1875. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 87 

STiade. — Orange. Offered by 2 out of 12 sources. 

18. Trade names. — Chrysoidin R; Cerotin Orange; C extra; Gold 
Orange for cotton. 

Name under wMch it was offered on the United States marlcet as a 
food color in 1907. — Chrysoidin R. 

Scientific name. — ^Anilin-azo-meta-tolylene-diamin. 

Shade. — Yellow brown. Offered by 1 out of 12 sources. 

41. Trade name. — Chrysoidin R. 

Scientific name. — Hydrochlorid of toluene-azo-meta-tolylene-di- 
amin. 

Discovered. — 1876. 

Shade. — Orange Brown. 

(Note. — It has not been possible accurately to differentiate in the literature as to 
whether Nos. 17, 18, or 41, or all three, were referred to.) 

FAVORABLE. 

1, YIeyl (p. 115): " Nonpoisonous * * * Chrysoidin * * *." 

2. Permitted by the law of Italy. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

2. Weyl {p. 126): Experiment on dog, giving him 113 milligrams per kilogram body 

weight, or 79 grains per 100 pounds body weight, produced a slight albuminuria. 
In a second experiment a dog receiving "1 grain" ("grain" is evidently a 
misprint for ''gram" and will be so treated), that is, 105 milligrams per kilogram 
body weight, or 74 grains per 100 pounds body weight, daily for one month, did 
not produce albuminuria, but caused a loss of body weight of about 12.5 percent. 
A third dog receiving about 2 milligrams per kilogram body weight, or about 1.5 
grains per 100 pounds body weight subcutaneously, suffered a loss of 20 per cent 
of its body weight in 23 days; dose repeated 24 days after and animal kept 
under observation seven days longer when animal was normal. 

3. Weyl in summarizing experiments on these three dogs concludes as follows: 

"Chrysoidin produces, according to my investigations, a slight albuminuria, 
and notable reduction in body weight, but further disturbance has not been 
noted." {p. 127.) 

4. Fraenkel {p. 577): "The above-mentioned Chrysoidin * * * produces a 

slight albuminuria, and a notable decrease of body weight, and produces factory 
eczema." 

5. Lewin (Lehrbuch der Toxikologie, 1897, p. 231): " Produces eczema, " and cites 

Deutsche Med. Wochenschr., 1891, p. 45. 

G. T. 28. 

Trade name. — ^Archil Substitute V. 

Scientific name. — Sodium salt of para-nitrobenzene-azo~alpha-naph- 
thylamin-para-sulphonic acid. 
Discovered and patented. — 1878. 
Shade, — Red. Not offered. 



88 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. WEYL(p.ii5): "Nonpoisonous * * * Archil Substitute * * *." 

Describing experiments on three dogs, as follows: A. 430 milligrams per 
kilogram body weight, or 301 grains per 100 pounds body weight, on each of two 
successive days, and double the dose on the fourth day, producing no vomiting, 
but a tendency to vomit, a slight albuminuria and colored urine. B. 182 mil- 
ligrams per kilogram body weight, or 1,27 grains per 100 pounds body weight, 
administered daily for one month; results similar to foregoing, but no colored 
urine, C. 105 milligrams per kilogram body weight, or 116 grains per 100 pounds 
body weight administered subcutaneously, produced only slight albuminuria, 
and no reduction in body weight, {-p. 125.) 

G. T. 43. 

Trade names. — Orange GT; Orange RN; Orange O; Orange N. 
Scientific name. — Sodium salt of toluene-azo-beta-naphthol-sulpho- 
nic acid. 

Discovered. — 1879. 

SJiade. — Orange. Not offered. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

UNFAVORABLE. 

1. Excluded by Austrian law. 

2. Excluded by Swiss laws. 



G. T. 55, 



Trade names. — Ponceau R; Ponceau 2 R; Ponceau G and GR; 
Xylidin Red; Xylidin Scarlet. 

Names under which it was offered on the United States marJcet as a 
food color in 1907, — Scarlet; Orange R. 

Scientific name. — Sodium salt of xylene-azo-beta-naphthol-disul- 
phonic acid. 

Shade. — Scarlet. Offered by 2 out of 12 sources. 

F'AVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. SI): "According to Cazeneuve and Lepine's experiments the follow- 

ing are not poisonous to human beings and dogs * * * Ponceau R * * *." 

3. "Ponceau R (Ponceau 2 R, Xylidin Red, Xylidin Ponceau), not poisonous to dogs 

neither by administration by stomach nor injection into blood. " (p. 115.) 

4. " Other Azo colors * * * 'Xylidin Red * * * are entirely nonpoisonous." 

{p. 148.) 

5. Fraenkel (p. 575): "That the monazo coloring matters examined by Cazeneuve 

and Lepine, as already above stated, were nonpoisonous, can be easily explained 
by the constitution of these substances. These two investigators examined 
* * * Ponceau R * * *." 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



89 



10. 



LiEBER (p. 140): A guinea pig received 310 milligrams per kilogram body weight 
or 217 grains per 100 pounds body weight, once a day six times every other day; 
the appetite appeared to remain good, and no disturbances were noted. 

Permitted by Austrian law. 

Permitted by Swiss laws. 

Cazeneuve and Lepine {Bull, de Vacad. de med., 1886, p. 643): Tolerated by 
man well or sick. 

Chlopin {p. 150) classes it as nonpoisonous on his own experiments. His experi- 
mental data are as follows: 

Experimental data by Chlopin. 
[1 grain=141 mg=99 grains.] 



Date. 


Dose. 


Weight. 


24-hours' 
urine. 


General condition of animal and urine. 


1902. 
May 3 


Grams. 
2 


Kilos. 
7.1 


cc. 
370 
351 
420 
290 
359 
360 
330 


Dog and urine normal and no albumen. 
Urine rose-colored; no albumen. 


5 


2 




Color normal; no albumen. 


6 




Rose-colored urine; no albumen. 


7 


2 




Normal color; no albumen. 


8 




Rose-colored; no albumen. 


9 






Color and composition normal. 








Total. 


6 





' UNFAVORABLE. 

1. Prohibited by the ordinance of the police commissioner in France. (See Lieher, 

p. 30.) 

2. Meyer (/. Amer. Chem. Soc. 1907, v. 29, pp. 900-901): The dog experimented 

on showed signs of paralysis on the morning of the seventh day at 8 o'clock, 
and died at 10.40 a. m., after having received a total of 32 grams of color, of 
which 16 had been given on the last day. The initial dose was 70 grains per 
100 pounds body weight; the total weight of color was 5,818 milligrams per 
kilogram body weight, or 4,073 grains per 100 pounds; the average daily dose 
was therefore 582 grains per 100 pounds, or 831 milligrams per kilogram body 
weight. 

DOUBTFUL, 

1, WiNOGRADOw (Zts. Nohr. Genussm., 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 65. 

Trade names. — Fast Red B; Bordeaux B; Bordeaux BL; Bordeaux 
R extra. 

Names under which it was offered on the United States mar'ket as a 
food color in 1907. — Bordeaux B; Claret Red. 

Scientific name. — Alphanaphthylamiii-azo-betanaplithol-disulplio- 
nic acid. 

Discovered. — 1878. 

Shade. — Red. Offered by 2 out of 12 sources. 



90 COAL-TAR COLOES USED IN FOOD PEODUCTS. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 115): "Bordeaux Red (Fast Red B) not poisonous to human beings." 

3. "Other Azo colors * * * Fast Red B ^ * * are entirely nonpoisonous.'* 

(p. 148.) 

4. Fraenkel (p. 575): "That the monoazo coloring matters examined by Cazeneuve 

and Lepine, as already above stated, are nonpoisonous, can be easily explained 
by the constitution of these substances. These two investigators examined 
^ ^ * Bordeaux B." 

5. Arloing and Cazeneuve {Archives de physiologie, 1887, pp. 356-393): As a result 

of this work, which is divided into three parts — (1) Stating the effect of direct 
introduction of the color into the circulation; (2) intravenous injections; (3) 
comparing the effects of injections of color and of salt; and (4) feeding by the 
mouth — these investigators conclude that these coloring matters are toxic only 
in extremely large doses; that when given to dogs with their food that no incon- 
venience of any kind results; this is based upon experiments on three dogs, 
covering 145 days, where each dog received per kilogram of initial body weight 
in the first case 20,307 milligrams, or 14,213 grains per 100 pounds initial body 
weight; in the second case, 29,590 milligrams, or 20,713 grains per 100 pounds 
initial body weight; and in the third case, 28,154 milligrams, or 19,758 grains 
per 100 pounds initial body weight. Per day this means 98 grains per 100 
pounds initial body weight in the first case; in the second case, 143 grains per 
100 pounds initial body weight; and in the third case, 137 grains per 100 pounds 
initial body weight. 

6. Cazeneuve {Arch. gen. de med., 1886, p. 753) says it may be taken without effect 

by man or animals, sick or well, in large doses. 

7. Cazeneuve and Lepine {Bull, de Vacad. de med., 1886, p. 643): Tolerated by man 

well or sick. 

G. T. 70. 

Trade name. — Azarin S. 

Scientific name. — Ammonium bisulphite compound of dichloro- 
phenol-azo-beta-naphthol. 
Shade. — Red. Not offered. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (j9. ii5): "Nonpoisonous * * * Azarin S * * *. " 

3. Experiments on five dogs; three fed by the mouth; two treated hypodermically, 

of which latter one died. The first dog received 1,367 milligrams per kilogram 
body weight in 25 days; that is, 54.7 kilograms per day on the average, or a total 
of 957 grains per 100 pounds of body weight; that is, 38 grains per 100 pounds 
body weight per day. The second dog received a total of 1,942 milligrams per 
kilogram body weight in 20 days, or 97 milligrams per kilogram body weight per 
day, which amounts to a total of 1,359 grains per 100 pounds body weight, or 68 
grains per 100 pounds body weight per daJ^ In both cases a distinct amount of 
albumen was present in the urine, and the urine evolved sulphurous acid on treat- 
ment with hydrochloric acid. The third dog received hypodermically three 
doses in eight days, each dose being 213 milligrams per kilogram body weight; 
that is, 149 grains per 100 pounds body weight; no bad effects, {p. 133.) 

3. "Administered by the stomach Azarin S is harmless. " {p. 134.) 

4. "Other Azo colors, * * ^ for instance Azarin S, are entirely nonpoisonous." 

(p. 148.) 

5. Fraenkel {p. 578) : "Azarin S administered by the stomach is entirely harmless. " 



COMPILED DATA UNDER GEEEN TABLE NUMBERS. 



91 



UNFAVORABLE. 

1. Weyl (p. 134)' Dog; weight not given; received 5 cc of Azarin S paste by injec- 

tion into the abdominal cavity, and survived three days. "The cause of death 
was considered to be peritonitis without effusion. The result of this post- 
mortem is of much interest. The red spots consisted, as was determined by 
chemical analysis, of the azo color which is the basis of the Azarin S. Conse- 
quently in the peritoneal cavity the same splitting up of the Azarin S had 
occurred which takes place when it is attached to textiles, " 

2. Fraenkel (p. 578): To the same effect. 

G. T. 78. 

Trade name. — Erika B. 

Scientific name. — Sodium salt of methyl-benzenyl-amido-thio- 
xylenol-azo-alpha-naphthol-disulphonic acid. 
Discovered and 'patented. — 1889. 
STiade. — Rose Pink. Not offered. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin {p. 153) : Based on his own experiments considers it as not harmless. The 
experimental data are as follows : 

Experimental data by Chlopin. 
[1 gram=125 mg=87.5 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 9 
10 


Grams. 
2 


Kilos. 
8.0 


cc. 
392 
400 
420 
360 
390 
293 
350 
390 
402 
350 


Dog normal; urine acid; no albumen. 

Urine of rose shade; insignificant traces of albumen; acid. 


11 






Color same; no albumen. 


12 


2 




Do. 


13 




Do. 


14 






Urine yellow, greenish shade; traces of albumen. 
Color normal; no albumen. 


15 






16 
17 


2 


8.2 


Do. 
Urine wine yellow, orange, acid; no albumen. 


18 






Dog quite well; urine orange; no albumen. 








Total . 


6 





G. T. 84, 



Trade names. — Resorcin Yellow; Tropseolin O; TropaeoKn II ; 
Chrysoin; Chryseolin; Yellow T; Gold Yellow; Acme Yellow. 

Names under wJiicJi it was offered on tlie United States marlcet as a 
food color in 1907. — Chrysoin REZ; Resorcin 0275. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-resorcinol. 

Discovered. — 1875. 

Shade, — Reddish yellow. Offered by 2 out of 12 sources. 



92 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



FAVORABLE. 

1. Chlopin {pp. 131-2) examined this color physiologically, and has classified it as 
harmless. The experimental data are as follows: 

Experimental data by Chlopin. 

No. 1 (p. f^7). 
[1 gram=43 mg=30 grains,] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 9 
10 


Grams. 


Kilos. 
23.00 


cc. 
500 


Dog quite well; urine normal color, acid; no albumen. 


11.21 
2 0.70 
12.00 


11 






Urine acid; no albumen. 


12 






No symptoms of poisoning; eats. 


13 




460 
520 
580 


14 






Do. 


17 






Urine normal color; no albumen; dog is well. 










Total.. 


13.21 
2 0.70 





No. 2. 
[1 gram=156 mg=109 grains.] 



1901. 
Oct. 9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22-26 

Total... 





6.4 


30 

350 


2 
2 






300 
335 
290 
290 
375 
300 


2 










2 






2 






320 
360 
360 












7.0 






10 



Dog well; urine yellow; no albumen. 

Do. 
Urine brown, acid; no albumen. 
Urine light brown, acid; no albumen. 

Do. 

Do. 

Do. 

Do. 

Do, 

Do. 
Urine light brown, acid, no albumen; diarrhea. 
Brown yellow, acid, no albumen no diarrhea. 
Urine normal; dog is well. 

Do. 



1 Internally. 2 Subcutaneously. 

2. Permitted by the law of Italy. 

UNFAVORABLE. 

1. Forbidden by the Confectioners' List. 

DOUBTFUL. 

1. WiNOGRADOw {Zts. Nohr. Genussm., 1903, v. 6, p. 589) says it noticeably retards 
digestive action; not indifferent. 

G. T. 85. 

Trade names. — Orange I; Alphanaphthol Orange; Naphthol Orange; 
Tropaeolin 000; Orange B. 

Names under which it was offered on the United States marJcet as a 
food color in 1907. — Orange RZ; Orange 027. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-alpha- 
naphthol. 

Discovered. — 1876. 

Shade. — Orange. Offered by 2 out of 12 sources. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 93 

FAVORABLE, 

1. Permitted by Confectioners' List. 

2. Weyl {p. SI): "According to Cazeneuve and Lepine's experiments, the following 

are not poisonous to human beings and dogs: * * * Orange * * *■," 

3. "Orange I (Alpha-naphthol Orange, Tropaeolin 000) not poisonous to dogs neither 

by administration by stomach, nor by injection into blood." (On authority of 
Cazeneuve and Lepine.) (p. 115.) 

4. Weyl {pp. 123, 148) refers to this as not poisonous. 

5. Permitted by the law of Italy. 

6. Permitted by the law of Austria, 

7. Cazeneuve {Arch. gen. de mid., 1886, Vol. I, p. 753) says it may be taken without 

effect by man or animals, sick or well, in large doses. 

8. Cazeneuve and Lepine {Bull, de Vacad. de med., 1886, p. 643): Tolerated by man, 

well or sick. 

G. T. 86. 

Tradenames. — Orange II; Bet anaphthol Orange; TropaeoHn 000 
No. 2; Mandarin G extra; Chrysaurein; Gold Orange; Orange extra; 
Atlas Orange; Orange A. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Naphthol Yellow SLOZ; Orange II; Orange; 
Orange Y; Mandarin G extra; Orange A 1201; Orange A extra. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-beta- 
naphthol. 

Discovered. — 1876. 

Shade. — Orange. Offered by 8 out of 12 sources. 

FAVORABLE. 

1. Permitted by law in Italy. 

2. Frentzel {Zts. Ndhr. Genussm.,1901, v. 4, p. 974) says that according to his experi- 

ments this color, in the small amounts in which it is used in food products and 
which can enter the human system in the course of 24 hours, can hardly, even 
with frequent administration, cause a harmful effect. 

3. Frentzel {Zts. Nahr. Genussm., 1901, v. 4, pp. 565-97^) : Experimented on rabbits, 

giving dye with food, a total of 21 grams in 19 days, a total of 8,748 milligrams 
per kilogram body weight, or 6,133 grains per 100 pounds body weight, in doses 
of 1 gram each, daily for the first 15 days, or about 417 milligrams per kilogram 
of body weight, or 292 grains per 100 pounds body weight per dose for these 15 
doses; the color could only be detected in the urine, and the feces became 
softer. A dog was given 1,020 milligrams per kilogram body weight, or 714 
grains per 100 pounds body weight, and showed distinct kidney irritation, great 
thirst, and diarrhea; recovery required about one week; and thereafter the same 
animal was fed by the mouth one-twentieth of the above dose each day for 9 
successive days without any untoward effect. A second dog received per kilo- 
gram of body weight 172 milligrams, or 121 grains per 100 pounds body weight, 
and it, like the first dog, in the first experiment, showed kidney irritation, 
diarrhea, and great thirst. On humans 100 milligrams, or IJ grains, colored 
the urine within 15 minutes, and this color remained for 24 hours; there was no 
sign of vomiting or diarrhea; the bitter taste of the color was noticeable. 



94 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

UNFAVORABLE. 

1. Forbidden by Confectioners' List, 

2. Forbidden by Swiss Analytical chemists. 

3. Weyl (p. 115): "Poisonous Orange II. * * *." 

4. " Betanaphthol Orange is, therefore, according to Experiment I, poisonous in 

small doses when administered by the stomach, and suffices to kill an ordinarily 
large strong dog." (p. 123) 

5. A. Weyl's own experiments on two dogs, the initial dose in one case being 476 

milligrams per kilogram body weight, or 333 grains per 100 pounds body weight; 
the animal receiving in the course of 20 days, in four doses, 1,333 milligrams 
per kilogram body weight, or 933 grains per 100 pounds body weight; or 335 
milligrams per dose per kilogram body weight; that is, 225 grains per dose per 
100 pounds body weight. The animal died, and suffered diarrhea and albumi- 
nuria, and its urine was colored red throughout the entire period. B. The 
second dog received hypodermically per kilogram body weight, 116 milligrams, 
or 61 grains per 100 pounds body weight; its urine was colored; albuminuria, 
diarrhea, loss of hair, abscesses, and loss of weight occurred. It required 36 
days to recover from four doses administered during one week. C. A rabbit 
received 1,333 milligrams per kilogram body weight, or 933 grains per 100 
pounds body weight, and died within 12 hours, (p. 122) 

6. "Of the 23 Azo colors subjected to examination only two * * * Orange II 

produce(s) such effects when administered by the stomach that we can con- 
sider it poisonous. With dogs the lethal dose is less than 1 gram per kilo of 
the body weight of Orange n * * *. " (p. 147,) 

7. "Further Orange II, which is poisonous * * *." 

8. "The poisonous qualities of Orange II." 

9. "Further, in spite of the presence of the sulpho groups, colors may be poisonous, 

as is shown with Orange II." (p. 148.) 

10. Chlopin {Zts. Ndhr. Genussm., 1902, v. 5, p. 241): A. A dog received 349 milli- 

grams per kilogram body weight, or 244 grains per 100 pounds body weight for 
the first day of experiment, which dose was repeated on the third and fourth 
days; nothing untoward is noted for the first three days in the condition of the 
dog; the urine was dark red but free from albumen; on the fifth and sixth days 
two-thirds of the above amount was given, and on the seventh and eighth days 
the original dose was given. On the fourth day the animal was frisky and had 
a good appetite but was vomiting; on the fifth day vomiting stopped, but 
diarrhea ensued, which diarrhea continued for one week; the weight remained 
practically constant; the urine was colored throughout from dark red to orange 
red and dark brown and became normal the fourth day after the last administra- 
tion . B . Humans : Chlopin took 200 milligrams, or 3-^ grains, in a gelatin capsule 
at 3 p. m.; at 4.30 p. m. the urine was colored a strong red orange; at 6 p. m. 
a dryness of throat and bad taste in mouth appeared; at 6.30 p. m. felt very 
badly; vertigo and unable to remain seated and continue writing; blood rushed 
to head; the general condition very poor; somewhat improved by moving 
about in open air; 7.30 felt so poorly took Glauber's salt as an antidote; 11 p. m. 
ill condition still continuing; urine normal yellow; midnight recovered. 

Chlopin states that he would not repeat this experiment on himself, or on 
any other human, and he concludes therefore that this color must be regarded 
as harmful. 

11. Chlopin (p. 133) classes it as "harmful." The experimental data are as follows: 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



95 



Experimental data by Chlopin. 
[1 graTn=116 ing=81 grains.] 



Date. 


Dose. 


Weight. 


24-liours' 
urine. 


General condition of animal and urine. 


1901. 

May 27 
28 


Grams. 
3 


Kilos. 
8.6 


cc. 
350 
340 
350 
350 

325 
330 
350 
315 
375 


Dog is quite well; urine normal. 
Urine brown red, acid; no albumen. 


29 


3 
3 

2 
2 
3 
3 




Do. 


30 




Diarrhea and vomiting at night, no albumen; urine orange red, 
acid, no albumen. 


31 




Jmie 1 




Diarrhea continues; dog lively, eats with relish; no albumen. 


2 





3 

4 


8.2 


Urine clear; no albumen; diarrhea continues. 
Urine dark brown; no albumen; diarrhea decreases. 


5 






Diarrhea still less; no albimien. 


6 




8.59 




Diarrhea very slight; urine slightly orange, no albumen. 
Urine normal in color and composition; diarrhea stopped. 


8 




350 










Total.. 


19 







12. Buss lists it as poisonous. 

DOUBTFUL. 

1, WiNOGRADOW (Zts. Nahr. Genussm., 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 87. 

Trade names. — Orange III; Helianthin; Tropseolin D; Methyl 
Orange; Dimethylanilin Orange. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-dimethy- 
lanilin. 

Discovered. — 1876. 

Shade. — Orange Yellow. Not offered. 

FAVORABLE. 

1. Permitted by the law of Italy. 

UNFAVORABLE. 

1. Chlopin (pp. 145, 146) on his own experiments classes it as poisonous. The 
experimental data are as follows : 

Experimental data hy Chlopin. 
No.l. 
[1 gram=163 mg=114 grains.] 



Date. 



Dose. 



Weight. 



24-hours' 
unne. 



General condition of animal and urine. 



1901. 
Aug. 29 



Grams. 



Kilos. 
6.14 



Sept. 



310 

250 
330 
305 
305 



5 
6 

7 
8-9 



Little. 
Little. 
Little. 



Total.. 



Before experiment dog quite normal; color urine usual, acid, 
no albumen. 
Do. 

Color of urine dark yellow; no albumen. 

Urine brown; reddish with sulphuric acid; no albumen. 
Do. 
Do. 
Do. 
Do. 

Urine dark brown; no albumen; vomiting. 

Paresis of hind legs; dog does not eat, but drinks with avidity. 

Complete ataxia, which became general on the 9th; dog can not 
move in straight line, and walks in circles, and drops his head 
on things and falls; after falling arises with difficulty and 
stands with widely spread feet, continuously lifting now one 
then the other; extremities shake; on 11th day sat with diffi- 
culty; placed on his feet, maintained equiUbrium with dif- 
ficulty; involuntarily Ufts one paw and moves it about in the 
air; animal can still swallow; eyes respond to light; does not 
eat; on the 12th the hind legs completely paralyzed; on the 
14th vomiting and paralysis of the front legs; lies quietly 
without moving; is killed. Autopsy shows no change in in- 
ternal organs except hypersemia in the lumbar region of the 
"spinal column (?) bordering between anterior and lateral 
columns," causing death by paralysis of the heart. 



96 



COAL-TAR COLORS USED IN FOOD PRODUCTS, 
Experimental data by Chlopin — Continued. 

No. 2. 
[1 grain=149 ing=104.3 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Dec. 3 


Grams, 
3 


Kilos. 
6.7 


cc. 


A few hours after giving color dog in tremors; does not eat. 
Urine black; acid; no albumen; paralysis of the extremities. 
Dog lies in cage in full paralysis; died before dinner; no albu- 
men in urine; cause of death, paralysis of heart. 


4 


Little. 
Little. 


5 













2. Meyer (/. Amer. Chem. Soc, 1907, v. 29, p. 900): Dog receiving 113 milligrams 
per kilogram body weight; that is, 79 grains per 100 pounds body weight. Result, 
diarrhea, which continued throughout 17 days, although only 3 doses of the 
same size were given in 6 days; thereafter the dose was increased geometrically; 
the diarrhea continued; the coloring matter was discharged in the urine and 
the feces; there was no abnormal condition revealed by the autopsy. 

DOUBTFUL. 

1. WiNOGRADOw {Zts. Nohr. Genussm., 1903, v. 6, p. 589) says it noticeably retards 
digestive action; is not indifferent. 

G. T. ^^. 

Trade names. — Diphenylamin Orange; Orange IV; Tropseolin 00; 
Orange M; Fast Yellow; Orange G S; New Yellow; Orange N; Acid 
Yellow D. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-diphenyl- 
amin. 

Discovered. — 1876. 

Shade. — Orange Yellow. Not offered. 

FAVORABLE. 

1. Weyl {p. 115): " Nonpoisonous * * * Diphenylamin Orange * * * 

2. * * * Diphenylamin Orange is * * * nonpoisonous." (p. 132.) 

3. "For instance, the poisonous Metanil Yellow corresponds to the nonpoisoiious 

Diphenylamin Orange." {p. 148.) 

4. The experiments on which Weyl based the conclusions above may be summarized 

as follows: A. A dog received 183 milligrams per kilogram body weight, or 
128 grains per 100 pounds body weight. The urine was rendered black, and 
contained traces of pheAol and abundant albumen; this condition lasted for 
72 hours, at the end of which 110 milligrams per kilogram body weight, or 
77 grains per 100 pounds body weight, were administered; urine became 
colorless and albumen diminished. Five days afterwards a total of 10 grams, 
or 366 milligrams per kilogram body weight, or 256 grains per 100 pounds 
body weight, were administered; the urine became abundant, was strongly 
black, alkaline, contained albumen. The loss of weight was 1 kilogram, or 
about 3| per cent. B. A dog received 308 milligrams per kilogram, or 216 grains 
per 100 pounds body weight, as the initial dose; albuminuria did not result 
until after repeated dosing same as initial dose, and administered for 2 weeks. 

5. Weyl's conclusions are as follows: "According to the above investigations, 

Diphenylamin Orange causes albuminuria, but further disturbances did not 
appear during the several weeks' observations on the animals used," 



COMPILED DATA UNDER GKEEN TABLE NUMBEES. 



97 



6. Chlopin {p. 148) examined this color and classes it as nonpoisonous. The ex- 
perimental data are as follows: 

Experimental data hy Chlopin. 

[1 grain=145 ing=100 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Oct. 27 
28 


Grams. 
3 


Kilos. 

7 


cc. 
300 


Dog quite normal; urine color normal; no albumen. 
Urine dark brown; acid; no albumen. 


29 


3 
3 
3 
3 
3 
3 






Do. 


30 






Do. 


31 






Do. 


Nov. 1 






Urine yellow, with sulphuric acid red; no albumen. 
Orange with orange sheen; no albumen. 


2 




340 


3 


6.5 


4 


275 
300 


Urine brown yellow; acid; no albtimen. 


5 


3 




Do. 


6 


6.7 


Do. 










Total . 


24 





7. Fraenkel {pp. 577, 578) to the same effect as Weyl, as above. 

8. Permitted by the law of Italy. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

G. T. 89. 

Trade names. — Brilliant Yellow S; Yellow WK,; Curcumin. 

Names under whicli it was offered on the United States marlcet as a 
food color in 1907. — Brilliant Yellow S. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-diphenyl- 
amin-suphonic acid. 

SJiade. — Yellow. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. LiEBER {p. 136): A very young rabbit received six doses on alternate days, each 
dose amounting to 320 milligrams per kilogram of body weight, or 224 grains per 
100 pounds of body weight. No untoward symptoms are recorded; the body 
weight increased almost 10 per cent in 11 days. 



Nothing. 



UNFAVORABLE. 



G. T. 92. 



Trade names. — Azo Acid Yellow; Azoflavin; Azo Yellow; Indian 
Yellow. 

Scientific name. — Mixture of iiitrated diphenylamin yellow with 
nitro-diphenylamin. 

Discovered. — 1880. 

Stiade. — Yellow. Not offered. 

97291°— Bull. 147—12 7 



98 



COAL-TAE COLORS USED IN FOOD PRODUCTS. 



FAVORABLE. 

1. Chlopin (p. 128) examined this color and classifies it as nonpoisonous. ■ The ex- 
perimental data are as follows: 

Experimental data by Chlopin. 

No. 1. 

[1 grani=125 ing=87.5 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and uriae. 


1901. 
Apr. 6 


Grams. 
2 


Kilos. 
8 


cc. 
370 
Little. 


Dog normal; urine acid; no albumen. 
Urine reddish orange; acid; no albumen. 


10 


3 




Do. 


11 




600 
430 


Urine red; no albumen. 


12 






Urine almost normal color; acid; no albumen. 











Total . 


5 





Conclusion: Nonpoisonous. 



No. 2 (p. 129). 
[1 gram= 143 mg= 100 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 12 
14 


Grams. 
2 
3 


Kilos. 

7 


cc. 
430 
610 
600 
400 


Dog normal; urine acid; no albumen. 
Do. 


15 




Urine dark yellow; acid; no albumen. 


16 






Urine almost normal color; acid; no albumen. 










Total.. 


5 





Conclusion: Showed no harmful effects. 
2. Permitted by law in Italy. 

UNFAVORABLE. 

Nothing. 

* DOUBTFUL. 

1. WiNOGRADow {Zts. NaJiT. Geuussm., 1903, v. 6, p. 589) says it almost completely 
inhibits digestion; noticeably retards digestive action; is not indifferent. 

G. T. 93. 

Trade name. — ^Azo-fuchsin G. 

Scientific name. — Sodium salt of para-sulphobenzene-azo-dioxy- 
naphthalene-sulphonic acid. 
Discovered. — 1 889 . 
Shade. — Reddish brown. Not offered. 



FAVORABLE. 



1. Chlopin {pp. 126, 127) examined this color and classifies it as nonpoisonous. The 
experimental data are as follows: 



COMPILED DATA UI^DER GREEN TABLE NUMBERS, 

Experimental data by Chlopin. 
No. 1. 
[1 gram=117 ing= 82 grains.] 



99 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901 
May 3 


Grains. 
2 


Kilos. 
8.5 


cc. 
300 
363 
390 
380 

285 
420 
292 


Dog well and normal; urine acid; no albumen. 
Urine chocolate brown; acid; no albumen. 


5 


2 




Do. 


6 




TTririP darV brown, chnnnlntp, in thin layer greenish sheen; acid; 


7 


2 




no albumen. 
TTrine slightly greenish; acid; nna.lbnmen. 


8 




Dark chocolate brown; acid; no albumen. 


9 




8.'7' 


Urine normal; dog is well. 








Total. 


6 





No. 2. 
[1 gram=125 mg=87.5 grains.] 



1901. 
Oct. 9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 

Total . 





8.0 


390 
310 


2 
2 






380 
325 


2 






2 
2 




396 






397 
325 
380 
246 
420 


2 












8.4 




12 



Dog quite nonnal; urine acid; no albumen. 

Do. 
Urine slightly more yellow; no albumen. 
Urine dark brown; acid; no albumen. 

Do. 

Do. 

Do. 

Do. 
' Do. 

Do. 
Urine almost black; acid; no albumen. 
Urine almost black; acid; no albumen; urine of lighter color. 

Do. 



Nothing. 



UNFAVORABLE. 



DOUBTFUL. 



1. WiNOGRADow (Zts. NaJiT. Genussm., 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 94. 

Trade names. — Tartrazin; Hydrazin Yellow. 

Names under whicli it was offered on the United States marJcet as a 
food color in 1907. — Flavazein Red Shade Z; Tartrazin; Acid Yel- 
low AT. 

Scientific name. — Sodium salt of benzene-azo-pyrazalone-carboxy- 
disulphonic acid. 

Discovered. — 1884. 

SJiade. — Yellow. Offered by 6 out of 12 sources. 

DOUBTFUL. 

1. LiEBER (p. 134)'- Dog, 2 months old, received, per kilo, body weight, 37 milli- 
grams, or 26 grains per 100 pounds body weight, six times, on alternate days. 
The animal suffered from mild diarrhea at the start, which continued with 
greater or less activity than at the start throughout the test. 



100 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

2. Meyer (/. Amer. Chem. Soc, 1907, v. 29, p. 897): Dog received 100 milligrams 
per kilogram body weight, or 70 grains per 100 pounds, increased in geometric 
proportion for 6 consecutive days, at the end of which time diarrhea set in. 
On that day 2,000 milligrams per kilogram body weight, or 1,400 grains per 100 
pounds body weight, were administered; this was about two-thirds as much as 
the animal had received in all the 5 days preceding; the feces were colored 
after the first administration, and the urine was also colored; albuminuria 
doubtful, 
3. Fraenkel (pj). 210 and 216): Tartrazin, according to the Green Tables, is a 
derivative of isopyrazolon; "* * * only those substances which are deri- 
vatives of pyrazolon are antipyretics, the isopyrazolon derivatives are, how- 
ever, poisonous." Tartrazin is also closely related to the antipyrin class of 
compounds, which class is known to possess an irritant action and also a de- 
pressing action on the circulation. Tartrazin also contains benzol groups, 
which are said to increase the physiological activity of pyrazolon derivatives. 

G. T. 95. 

Trade names. — Metanil Yellow; Orange MN; Tropseolin G. 

Names under wJiicJi it was offered on the United States marlcet as a 
food color in 1907. — Victoria Yellow cone. Z; Yellow MXX cone. 

Scientific name. — Sodium salt of meta-sulphobenzene-azo diphenyl- 
amin. 

Discovered. — 1879. 

Shade. — Orange. Offered by 2 out of 12 sources. 

FAVORABLE. 

1. Frentzel (Zts. Nahr. Genussm., 1901, v. 4, p. 974): A. A rabbit received 379 

milligrams per kilogram body weight, or 265 grains per 100 pounds body weight; 
no color administered for 2 days, and then administered at intermittent periods, 
so as to receive 6 doses in 19 days. Total weight administered per kilogram 
body weight 2,085 milligrams, or 1,460 grains per 100 pounds, which is equivalent 
to 77 grains per day per 100 pounds; the color could always be detected in the 
urine, and the feces became softer. B. A dog received 581 milligrams per 
kilogram body weight at one dose; that is, 407 grains per 100 pounds body weight. 
There was no vomiting and no diarrhea; the dye persisted in the urine for 72 
hours. C. The same dog, after recovering from the foregoing, received daily 
one-tenth the above dose for 9 days; the dyestuff was found in the urine and the 
feces and movements were normal; dissection showed nothing abnormal. 
D. A human swallowed 100 milligrams, or 1.5 grains; no untoward symptoms 
are recorded; the urine remained colored for 24 hours. From the foregoing 
Frentzel concludes that this coloring matter is absolutely harmless. 

2. Chlopin {Zts. Nahr. Genussm., 1902, v. 5, p. 241)'- A. A dog received 305 milli- 

grams per kilogram body weight; that is, 104 grains per 100 pounds body weight; 
no color administered for fom* days; the same dose was given on alternate days 
six times, and the dose was increased 50 per cent, and that dose administered 
twice, and the original dose was given on the next alternate day; altogether the 
animal received per kilogram body weight, 3,355 milligrams, or 1,144 grains 
per 100 pounds body weight, in a period of 22 days, or an average of 153 milli- 
grams per kilogram body weight per day, or 52 grains per day per 100 pounds 
body weight. At the end of the twelfth day albuminuria set in, and it required 
three weeks after ceasing the administration of the color ior the albuminuria 



COMPILED DATA UNDER GEEEN TABLE NUMBERS. 



101 



2. Chlopin {Zts. Nahr. Genussm., 1902, v. 5, p. ^4^)— Continued. 

to disappear; the urine was colored throughout the period of dosing, and it was 
not until 10 days after the last color had been administered that the urine 
regained normal color; otherwise the animal was well throughout. B. Hu- 
mans: Two hundred milligrams, or 3^^ grains taken at 3 p. m., October 30, 
1901, colored the urine so highly yellow that it could be dyed with. Apart 
from the bitter taste of the product no untoward symptoms are recorded. C. 
Chlopin's conclusion (Zts. Nahr. Genussm., 1902, v. 5, p. 244): "Metanil Yellow 
is not poisonous to dogs in doses of from 2 to 3 grams per day, nor to humans 
in doses of 0.2 grams per day, and may therefore perhaps be regarded as non- 
poisonous from a practical point of view." 



UNFAVORABLE. 

Weyl (p. 115): "Poisonous * * * Metanil Yellow." 
Says the product smelled strongly of diphenylamin. (p. 130.) 
A. ''Metanil Yellow must be considered poisonous when administered by the 
stomach from the indications of Experiments 1 and 2. The lethal dose, which 
is determined by Experiment 2, is 0.53 grams per kilo body weight." This 
lethal dose is 371 grains per 100 pounds body weight. B. A dog received 862 
milligrams per kilogram body weight, or 603 grains per 100 pounds body weight. 
This caused vomiting; the same dose was repeated 24 hours afterwards, the 
animal again vomiting. The animal died within 96 hours from the first admin- 
istration. C. A dog received 89 milligrams per kilogram body weight, or 62 
grains per 100 pounds body weight; the urine became colored about 96 hours 
after administration; 5 days after the first administration the animal was given 
10 times the original dose; vomiting set in within one hour; in 24 hours the 
urine was deeper colored; a week later after the dose last preceding, one-half 
of that dose was given, and the animal died within 24 hours; the animal had 
lost during this period approximately one-quarter its original weight, {p. 132.) 
li^ -x- * Metanil Yellow * * * produce[s] such effects when administered 
by the stomach that we can consider them [it] poisonous." {p. 147.) 

5. "The poisonous qualities of ^ ^ * Metanil Yellow; the poisonous Metanil 

Yellow." (p. 148.) 

6. Fraenkel {p. 578): "A dog weighing 11 kilograms was killed by 20 grams of 

this coloring matter within four days, whereas the isomeric Diphenylamin 
Orange is nonpoisonous, and it must first be considered if the poisonous nature 
of this substance can be explained by the easy liberation of diphenylamin 
from it, since this coloring matter, in and of itself, has a strong odor of diphenyla- 
min." 

7. Chlopin (p. 141)'- Based on his own experiments considers it "Not quite harm- 

less." The experimental data are as follows: 

Experimental data by Chlopin. 
[1 gram = 153 mg = ]07 grains.] 



4. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 18 


Grams. 


Kilos. 
6.55 


cc. 
390 
350 
308 
300 
370 


Quite normal. 


19 


2 




20 




Do 


21 






Urine orange; acid; no albumen. 
Do 


22 


2 




23 




Do. 


24 


2 




380 
332 
320 
365 


Do 


25 




Urine dark brown no albumen 


26 


2 




Do. 


27 




Do. 



102 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Experimental data by Chlopin — Continued. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 28 
29 


Grams. 
2 


Kilos. 


cc. 
330 
350 
350 
355 
400 
340 
330 
400 
305 
390 
330 
335 


Urine dark brown, no albumen. 




Do. 


30 


2 




Do. 


31 




Do. 


June 1 


2 




Urine brown* traces of albumen 


2 




Do. 


3 






Do. 


4 


3 




Do. 


5 




Do. 


6 


3 




Do. 


7 




Do. 


8 


2 




Do. 


9-29 


6.5 


Color ofurine normal June 18, on 29th albumen disappears. Dog 
is well. 








Total.. 


22 





8. Chlopin (p. 141)' On authority of others not stated, classes this color as harmful 

or poisonous. 

9. Prohibited by the laws of Italy. 

10. Prohibited by Confectioners' List. 

11. Prohibited by the Resolutions of the Society of Swiss Analytical Chemists, Sep- 

tember, 1891. 

12. Buss lists it as poisonous. 

] DOUBTFUL. 

I 1. WiNOGRADOW (Zts. Nohr. Genussm., 1903, v. 6, p. 589) says that it noticeably 
retards digestion. 

G. T. 97. 

Trade names. — Orange T; Mandarin G R; Orange R; Kermesin 
Orange. 

Name under wMcJi it was offered on the United States marTcet as a 
food color in 1907. — Orange 2 R. 

Scientific name. — Sodium salt of sulpho-ortho-toluene-azo-beta- 
naphthol. 

Shade. — Orange. Offered by 1 out of 12 sources. 



Nothing. 



FAVORABLE. 
UNFAVORABLE. 



1. Chlopin {p. 125): Based on his own experiments considers this color as "harm- 
ful." The experimental data are as follows: 

No.l. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 4 


Grams. 


Kilos. 


cc. 
310 
280 
420 
570 
370 
250 

330 


Nothing abnormal. 

Urine reddish brown; traces of albumen; acid. 

Do. 
Urine dark brown; acid; traces of albumen. 
Color of urine weaker; no albumen. 
Almost nonnal -colored urine; no albumen; dog i 

lively. 
Nothing abnonnal. 








6 


3 






7 






8 








9 






s well and 


10 
















Total.. 


4 





COMPILED DATA UNDER GREEN TABLE NUMBERS. 

No. 2. 
[1 gram = 217 mg = 152 grains.] 



103 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Jan. 25 

26 


Grams. 
2 


Kilos. 
4.6 


cc. 
200 


Soon after giving color heavy vomiting and diarrhea; dog does 

not eat or drink the rest of the day; urine acid; no albumen. 
Vomiting and diarrhea continued; dog is tired and run down, 


27 








and began to eat; urine dark brown and no albumen. 
Urine same; dog livelier. 


28 
29 


2 
2 


4.3 


180 
200 


Diarrhea and vomiting stopped; urine of brown color; acid; no 

albumen. 
Urine orange; no albumen; acid. 






Total.. 


6 





G. T. 102. 

Tradenames. — Fast Red; Roccellin; Cerasin; Rubidin; Fast Red 
A; Rauracienne; Orcellin No. 4. 

Scientific name. — Sodium salt of para-sulphonaphthalene-azo-beta- 
Qaphthol. 

Shade. — Brownish red. Not offered. 

Discovered and patented. — 1877. 

FAVORABLE. 

1. Permitted by the law of Italy. 

2. Permitted by the law of Austria. 

3. Cazeneuve {Arch. gen. de med., 1886, p. 753) says it may be taken without effect 

by man or animals, sick or well, in large doses. 

4. Cazeneuve and Lepine {Bull, de Vacad. de mid. 1886, p. 643): Tolerated by man 

well or sick. 

G. T. 103. 

Trade names. — Azorubin S; Carmoisin; Azo Acid Rubin; Fast Red 
C ; Azorubin A. 

Names under wTiich it was offered on tJie United States marlcet as a 
food color in 1907. — Claret Red RZ; Cardinal 3 B; Azorubin; Car- 
moisin B. 

Scientific name. — Sodium salt of para-sulphonaphthalene-azo- 
alpha-naphthol-para-sulphonic acid. 

Discovered and patented. — 1883. 

STiade. — Red. Offered by 6 out of 12 sources. 



FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Cazeneuve and Lepine: Not poisonous to human beings. 

3. Meyer (/. Amer. Chem. Soc. 1907, v. 29, p. 898): One hundred milligrams per 

kilogram body weight, or 70 grains per 100 pounds body weight administered, 
increased geometrically; diarrhea was marked only after administration of 
exceptionally large doses (the seventh day); the stools were deep violet and 
the urine was carmine, becoming dark; the autopsy developed nothing abnor- 
mal; the whole interior was of a red color. 



104 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



4. LiEBER (p. 138): A guinea pig received once a day six times every other day 
241 milligrams per kilogram body weight, or 169 grains per 100 pounds body 
weight; appetite remained good throughout, and aside from an occasional 
thirstiness noted no untoward observations were recorded. 

G. T. 105. 

Trade names. — Fast Ked E; Fast Red. 

Names under which it was offered on the United States marlcet as a 
food color in iP(97.— Claret Red RZ. 

Scientific name. — Sodium salt of para-sulphonaphthalene-azo-beta- 
naphthol-monosulphonic acid. 

Discovered and patented. — 1878. 

Shade. — Red. Offered by 1 out of 12 sources. 

FAVORABLE. 



1. Permitted by Confectioners' List. 

2. Meyer (/. Amer. Chem. Soc. 1907, v. 29, p. 898): Initial dose 100 milligrams per 

kilogram body weight or 70 grains per 100 pounds, and given three times 
increased geometrically once before diarrhea was observed; there was no 
albumen in the urine; urine was colored deep red; feces colored red at the 
start, at the end of the experiment chocolate brown; autopsy showed all parts 
to be substantially normal. 

3. Cazeneuve and Lepine {Compt. rend., 1885, v. 101, pp. 823-827): A. Dog: 

Weight 21.5 kilo, received as follows: 



Days. 


Grams. 


Milligrams 
per Mo. 


Grains per 
lOOpovmds. 


32 
20 

8 
10 

5 


0.500 
2.150 
4.300 
5.000 
10. 000 


23.2 
100.0 
200.0 
232.0 
462.0 


16.2 

70.0 

140.0 

162.0 

324 



Nothing abnormal except occasional greenish urine; no vomiting; no diarrhea. 
B. Man: 1. One of the experimenters took 1 gram, dissolved in wine, daily 
for 15 days; no effect. 2. A man aged 25, afflicted with albuminuria, received 
the following: 



Days. 


Grams. 


3 
2 

1 


0.5 
1.0 
2.0 



Caused colic without diarrhea; amount of urine or albumen not affected. 3. 
Three men afflicted with Bright's disease received each daily for 8 days 1 gram; 
no effect on the albumen. 4. A 30-year-old man chronic invalid took 4 grams 
one day, 6 grams the next day; no effect was observed. 



COMPILiED DATA UNDEE GKEEN TABLE NUMBEES. 105 

4. A^LOiNG AND Cazeneuve (ArcMves de physiologie, 1887, pp. 356-393): As the 
result of this work, which is divided into four parts: (1) Stating the effect of 
direct introduction of the color into the circulation; (2) intravenous injections; 
(3) comparing the effects of injections of color and of salt; and (4) feeding by 
the mouth — these investigators conclude that these coloring matters are toxic 
only in extremely large doses; that when given to dogs with their food no 
inconvenieace of any kind results; this is based upon experiments upon three 
dogs, covering 145 days, where each dog received, per kilogram initial body 
weight, in the first case, 20,307 milligrams, or 14,215 grains per 100 pounds 
initial body weight; in the second case, 29,590 milligrams, or 20,713 grains 
per 100 pounds initial body weight; in the third case, 28,154 milligrams, or 
19,758 grains per 100 pounds initial body weight. Per day this would mean 98 
grains per 100 pounds initial body weight in the first case; in the second case 
the daily dose was 143 grains per 100 pounds initial body weight; and in the 
third case the daily dose was 137 grains per 100 pounds initial body weight. 

G. T. 106. 

Trade names. — New Coccin; Cochineal Eed A; Brilliant Scarlet; 
Crocein Scarlet 4 BX. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Claret Red RZ; Crocein Scarlet; New Coccin; 
Scarlet L; Brilliant Scarlet 4 R. 

Scientific name. — Sodium salt of para-sulphonaphthalene-azo-beta- 
naphthol-disulphonic acid (G.). 

Discovered. — 1878. Offered by 5 out of 12 sources. 

Shade. — Red. 

FAVORABLE. 

1. Cazeneuve and Lepine. (See Weyl, p. 115.) 

2. Weyl {p. 31): '"^ * * not poisonous to human beings and dogs, * * * 

Purple ^ * ^" 

3. Cazeneuve and Lepine {Bull, de Vacad. de med., 1886, p. 643): Tolerated by man, 

sick or well, 

unfavorable. 
1. Prohibited by Confectioners' List. 

G. T. 107. . . 

Trade names. — Fast Red D ; Azo Acid Rubin 2 B ; Fast Red E B ; 
Bordeaux S; Amaranth. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Claret Red RZ; Red; Amaranth B (Azo color 
similar to) ; Bordeaux S; Naphthol Red S; Amaranth. 

Scientific name. — Sodium salt of para-sulphonaphthalene-azo-beta- 
naphthol-disulphonic acid (R). 

Discovered and patented. — 1878. 

Shade. — Red. Offered by 7 out of 12 sources. 



106 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

FAVORABLE. 

1. Cazeneuve and Lepine (see Weyl, p. 115): Not poisonous to human beings. 

3. Lieber (p. 148): A rabbit received 284 milligrams per kilogram body weight, or 

199 grains per 100 pounds once a day, five times every other day, aci aside from 

decreased appetite the second and third day of the observation period nothing 

untoward is noted. 
4 Weyl (p. 31): ''^ * * not poisonous to human beings aud dogs, * * * 

Purple * ^ ^" 
5'. Cazeneuve and Lepine {Bull de Vacad. de med., 1886, p. 64S): Tolerated by man, 

sick or well. 

G. T. 138. 

Tradenames. — Fast Brown G; Acid Brown. 

Scientific name. — Sodium salt of bi-sulphobenzene-disazo-alpha- 
naphthol. 

Discovered. — 1882. 

Shade. — Brown. Not offered. 

FAVORABLE. 

1. Weyl (p. 134): ''The following is a summary of the results obtained with the Dis- 
azo colors submitted to test by me, viz, Fast Brown G * * ^\ All these 
proved to be nonpoisonous * * *." A. A dog weighing 9.63 kilos received 
312 milligrams per kilogram body weight, or 218 grains per 100 pounds body 
weight; the same dose was repeated 48 hom-s afterwards, when diarrhea set in, 
and the urine was colored red; 24 hours afterwards 208 milligrams per kilogram 
body weight, or 146 grains per 100 pounds body weight were given; the urine 
was colored strongly red 24 hours thereafter. Eight days afterwards 520 milli- 
grams per kilogram body weight, or 364 grains per 100 pounds body weight, were 
administered; marked diarrhea set in; 3 days later the dose given was twice the 
dose last given, when severe diarrhea resulted, but unchanged color appeared in 
the urine, and continued for 24 hours afterwards ; diarrhea continued for 96 hours. 
Evidences of albuminuria apparently not dependable. B. A second dog, 
weighing 5.9 kilos, received 339 milligrams per kilogram body weight, or 237 
grains per 100 pounds body weight daily throughout an entire month; diarrhea 
was produced after 6 days, which continued almost during the month; appetite 
was diminished and the loss in weight was about 20 per cent on the original. 
C. Weyl concludes as follows: "According to these experiments, this color 
in continuous, though slight, doses, or in large doses, but less frequently, 
produces diarrhea, anorexia, and emaciation." {p. 136.) 

unfavorable. 

1. Prohibited by Confectioners' List. 

2. Weyl (p. 147): "Of the remaining colors * * * others (produce) diarrhea 

(Fast Brown ***)." 

G. T. 160. 

Trade name. — Crocein Scarlet 3 B; Ponceau 4 RB. 
Scientific name. — Sodium salt of sulphobenzene-azo-benzene-azo- 
beta-naphthol-monosulplionic acid. 
Discovered and patented. — 1881. 
Shade. — Scarlet. Not offered. 



COMPILED DATA UNDER GREEJST TABLE NUMBERS. 107 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

DOUBTFUL. 

1. Houghton (/. Amer. Chem. Soc, 1907, v. 29, pp. 1351-57): Hinders fibrin diges- 
tion at all strengths; at 1:200 hinders casein and albumen digestion. 

G. T. 163. 

Tradenames. — Biebrich Scarlet; Ponceau B; New Red L; Ponceau 
3 RB; Fast Ponceau B; Imperial Scarlet. 

Scientific name. — Sodium salt of sulphobenzene-azo-sulpho-ben- 
zene-azo-beta-naphthol. 

Discovered. — 1878. 

Shade. — Scarlet. Not offered. 

FAVORABLE. 

1. Permitted by law in Italy. (See Lieher, pp. 18, 22, 23.) 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

G. T. 164. 

Trade name. — Crocein Scarlet O extra. 

Scientific name. — Sodium salt of sulphobenzene-azo-sulphoben- 
zene-azo-beta-naphthol-sulphonic acid. 
Discovered. — 1888. 
Shade. — Scarlet. Not offered. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

G. T. 166. 

Trade name. — Wool Black. 

Scientific name. — Sodium salt of sulphobenzene-azo-sulphoben- 
zene-azo-para-tolyl-beta-naphthylamin. 
Discovered. — 1885. 
Shade. — Black. Not offered. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 134)'- "The following is a summary of the results obtained with the 

Disazo colors submitted to test by me, viz: * ^^ * Wool Black * * *. 
All these proved to be nonpoisonous * * *." 



108 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

3. A. A dog received 167 milligrams per kilogram body weight, or 117 grains per 
100 pounds body weight each day for 3 successive days; no color was admin- 
istered for the next 2 days, and the third day the dose was double thfe former 
dose. The urine was colored bluish-black and contained albumen. Two days 
afterward the same dose was given; urine of intense dark-blue color, and con- 
tained unaltered coloring matter, which disappeared in 48 hours. Albuminuria 
continued for about 15 days. {p. 137.) B, "Wool Black is nonpoisonous both 
by gastric and by subcutaneous administration." (p. 137.) 

G. T. 169. 

Trade names. — Crocein Scarlet 7 B; Ponceau 6 RB; Crocein 
Scarlet 8 B. 

Names under wJiich it was offered on the United States marlcet as a 
food-color in 1907. — Sodium salt of sulpho toluene- azo-toluene-azo- 
beta-naphthol-alpha-sulphonic acid. 

Discovered and patented. — 1881. 

Shade. — Red. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

G. T. 188. 

Trade names. — Naphthol Black B; Brilliant Black B. 

Name under which it was offered on the United States marJcet as a food- 
color in iP07.— Naphthol Black BDF. 

Scientific name. — Sodium salt of disulpho-beta-naphthalene-azo- 
alpha-naphthalene-azo-beta-naphthol-disulphonic acid. 

Discovered and patented. — 1885. 

Shade. — Black. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 138): A, A dog received 112 milligrams per kilogram body weight, or 

78 grains per 100 pounds body weight, daily for 3 successive days; distinct 
albuminuria, uncolored urine; blue-colored feces; thereupon the daily dose was 
increased to 187 milligrams per kilogram body weight, that is, 131 grains per 
100 pounds. No color was administered for 6 days, and during this time the 
urine was colored from reddish-violet to a bluish-black red ; thereupon the last 
dose was doubled and 24 hours afterwards that dose was doubled; rather much 
albumen in urine which was bluish; albuminuria continued for about a week. 
B. A dog received 222 milligrams per kilogram body weight, or 155 grains per 
100 pounds daily throughout a whole month; it remained entirely well with 
good appetite. 

3. "This color is harmless when administered by the stomach, but poisonous sub- 

cutaneously." (p. 140.) 

4. Schacherl: Not harmful under conditions in which it is used. 

UNFAVORABLE. 

1 Weyl (p. 139): Where a dog, receiving subcutaneously 31 milligrams per kilogram 
body weight, or 22 grains per 100 pounds body weight, subcutaneously, died 
apparently wholly as a result of the color. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 109 

2, "Naphthol Black P, however, is plainly poisonous when introduced into the sub- 
cutaneous cellular tissue." (p. Ufl ■) 

G. T. 197. 

Trade names. — Bismarck Bro^^^n; Phenylene Brown; Leather 
Brown; English Brown; Manchester Brown; Vesuvin; Cinnamon 
Brown. 

Names under which it was offered on the United States marlcet as a 
food-color in 1907. — Vesuvin 4B Cone. Z; Bismarck Brown; Bismarck 
Brown B No. 216; Bismarck Brown B. 

Scientijicname. — Hydrochlorid of benzene-disazo-phenylene-diamin, 

Discovered and patented. — 1863. 

Shade. — Reddish brown. Offered by 4 out of 12 sources. 

FAVORABLE. 

1, Weyl (p. 115): " Nonpoisonous Bismarck Brown." 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

2. Weyl {p. 117): A. A dog received 33 milligrams per kilogram body weight, or 

23 grains per hundred pounds body weight; in one and one-half hours, vomiting; 
next day same dose same result with the addition that the animal took no food 
and moved about but little for 48 hours; on the fourth day same dose, in two 
hours, vomiting; for 96 hours animal took no food; on the eighth day albumen 
in the urine and the animal ate; on the ninth day 83 milligrams per kilogram 
body weight or 58 grains per 100 pounds body weight, vomited for one-half hour 
after administration; for the next 5 days the animal took hardly any food; on 
the fourteenth day the animal improved, took food on the fifteenth day; traces of 
albumen in urine for 17 days longer, at end of which time animal recovered. 

B. A dog received 169 milligrams per kilogram body weight, or 118 grains per 
100 pounds body weight; in 24 hours the urine was colored brown; 48 hours 
after the first dose that dose was repeated, and unconverted color was found 
in the urine; 48 hours later the same dose was repeated; the color in the urine 
disappeared in 24 hours; 4 days later the dose was trebled, and the animal 
vomited, seemed sick for 4 days thereafter; on the fifth day recovery apparently 
complete. On the sixth day the last dose was repeated, and the animal vomited 
after the administration. It took no food for 24 hours, and was normal after 
48 hours. There was no albuminuria in this case. 

C. A dog received daily for an entire month 45 milligrams per kilogram body 
weight, or 31^ grains per 100 pounds body weight; it was in good health during 
the entire time, did not vomit, and ate as usual. Its gain in weight was 6^ 
per cent. 

3. "Bismarck Brown produces, when administered to dogs by the stomach, even 

in doses of 350 milligrams per kilogram body weight (245 grains per 100 pounds 
body weight), vomiting and albuminuria. Further disturbance is not noted 
even in large doses; small doses, 45 milligrams per kilogram body weight (or 
31 J grains per 100 pounds body weight), even when frequently administered 
seem to be entirely harmless. Doses of 16 milligrams are harmless even when 
introduced into the subcutaneous cellular tissue." (p. 118.) 

4. "Of the remaining colors some produce vomiting (e. g., Bismarck Brown 

* * *)." (p. 147.) 



110 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

5. Lewin (Lehrbuch der Toxikologie, 1897, p. 231): Produces eczema, and cites 

Deutsch Med. Wochenschr., 1891, p. 45. 

6. Fraenkel (p. 575): "When the Azo dyestuffs do not contain any sulpho group 

they are poisonous. Thus, for example, Bismarck Brown * * *. This 
produces no effect in small doses; on the other hand, doses of 350 milligrams 
per kilogram of animal (245 grains per 100 pounds) produce albuminuria and 
vomiting." 

DOUBTFUL. 

1. Houghton (/. Amer. Chem. Soc, 1907, v. 29, pp. 1351-1357): Hinders digestion 
of fibrin, casein and albumen, in strengths of 1:100 or 1:400. 

G. T. 201. 

Trade names. — Manchester Brown EE; Bismarck Brown R; 
Vesuvin B. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Vesuvin 4 B Cone. Z; Vesuvin B. 

Scientific name. — Hydrochlorid of toluene-disazo-meta-tolylene- 
diamin. 

Discovered and patented. — 1878. 

Shade. — Reddish brown. Offered by 2 out of 12 sources. 

UNFAVORABLE. 

1. Lewin (Lehrbuch der Toxicologie, 1897, p. 231): ''Produces eczema," and cites 
Deutsch. Med. Wochenschr., 1891, p. 45. 
Note. — The literature is not always conclusive as between Nos. 197 and 201, and 
probably most, if not all, the references under No. 197 also apply to No. 201. 

G. T. 240. 

Trade name. — Congo Red. 

Name under which it was offered on the United States marlcet as a 
food color in 1907. — Congo. 

Scientific name. — Sodium salt of diphenyl-disazo-binaphthionic 
acid. 

Discovered and patented. — 1884. 

Shade. — Red. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Weyl: "According to Experiments 1 and 2 Congo Red is, after long-continued 

administration by the stomach, harmless." 

2. A. A dog received 274 milligrams per kilogram body weight, or 192 grains per 100 

pounds ; this dose was repeated next day, when the urine became pale, was strongly 
alkaline and contained albumen; the next day the same dose was repeated, 
whereupon the urine was of a weak red color, and a little albumen present; 
the next day the dose was increased to 411 milligrams per kilogram body 
weight, or 298 grains per 100 pounds; the urine was somewhat reddish and con- 
tained a little albumen. No color was given for 6 days, at the end of which 
time the urine was reddish, and deposited a reddish sediment, probably Congo. 
At the end of that time the dose was increased to 685 milligrams per kilogram 



COMPILED DATA UNDER GREEN TABLE NUMBERS. Ill 

2. A. — Continued. 

body weight, or 480 grains per 100 pounds body weight; the urine was feebly 
alkaline and contained some albumen. The next day the dose last given was 
doubled; the urine was colored to such an extent that it could be dyed with. 
Two days later the same dose was repeated; animal took but little food, was 
otherwise comfortable; there was little albumen present. The loss in body 
weight was about 4^ per cent. (p. 141.) 
B. A second dog received 233 milligrams per kilogram body weight, or 163 grains 
per 100 pounds, daily for one month, and remained entirely well. 

G. T. 269. 

Trade name. — Chrysamin R. 

Name under which it was offered on the United States marlcet as a 
food color in 1907. — Chrysamin R. 

Scientific name. — Sodium salt of ditolyl-disazo-bisalicylic acid. 

Discovered and ^patented. — 1884. 

Shade. — Yellow. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 1S4)'. "The following is a summary of the results obtained with Disazo 

colors submitted to test by me, viz: Chrysamin R." ''All of these proved 
to be nonpoisonous, * * *." 

3. A. A dog received 515 milligrams per kilogram body weight, or 361 grains per 

100 pounds; urine became alkaline and yellowish, and easily dyed cotton; 
very little albumen. Within 24 hours the same dose was repeated, diarrhea 
resulting and vomiting for 3 days, whereupon the animal was given one-fifth of 
the dose, or 103 milligrams per kilogram body weight, that is, 72 grains per 100 
pounds body weight; the urine continued slightly colored, and contained a 
distinct amount of albumen, continuing for 2 days, when the last dose was 
repeated; 24 hours afterwards the dose was doubled, and repeated the next 
day; the day after the dose was increased 50 per cent; 3 days later the last 
dose was repeated; slight albuminuria set in, lasting 5 days. B . A dog received 
three doses of 619 milligrams each per kilogram body weight, or 433 grains per 
100 pounds body weight, three times in the course of 10 days; the urine was 
yellowish in color and contained very little albumen, (p. 145.) 

4. "Chrysamin is harmless when taken into the stomach." {p. 147.) 

5. ScHACHERL (p. 104-5) says Chrysamin is harmless under the conditions in which 

it is used. 

UNFAVORABLE. 

1. Weyij (p. 147): "Of the remaining colors some produced vomiting * * * 
others diarrhea (* * * Chrysamin R * * *.") 

G. T. 277. 

Trade names. — Benzopurpurin 4 B; Cotton Red 4 B; Sultan 
Red 4 B. 

Scientific name. — Sodium salt of ditolyl-disazo-binaphthionic acid. 
Discovered. — 1884-85. 
Shade. — Red. Not offered. 



112 

Nothing. 



COAL-TAK COLORS USED IN FOOD PRODUCTS. 

FAVORABLE. 

UNFAVORABLE. 



1. Chlopin (p. 130): On his own experiments classes it as suspicious. The experi- 
mental data are as follows : 

Experimental data by C?dopin. 









[1 gram=125 mg=87.5 grains.] 


Date. 


Dose. 


Weight. 


24-hoiir 
urine. 


General condition of animal and urine. 


1901. 
Apr. 16 
17 


Grams. 
2 


Kilos. 
8 


cc. 
300 
330 
450 
470 
370 
320 
310 
370 
310 


Dog is well, lively; urine normal color; acid; no albumen. 
Do. 


18 


3 




Vomiting several times; no albumen. 


19 




Urine yellow-orange; no albumen; no vomiting. 
Do. 


20 






21 


2 




Do. 


22 




Do. 


23 






Urine normal; dog is well. 
Do. 


24 














Total. 


7 





DOUBTFUL. 

1. Winogradow {Zts. Nahr. Genussm. 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 287. 

Trade name. — ^Azo Blue. 

Name under which it was offered on the United States marlcet as a food 
color in 1907. — ^Azo Blue. 

Scientific name. — Sodium salt of ditolyl-disazo-bi-alpha-naphthol- 
para-sulplionic acid. 

Discovered. — 1 885, 

Shade. — Grayish violet. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl {p. 134)'- The following is a summary of the results obtained with the Disazo 

colors submitted to test by me, viz: * ■* * Azo-blue, * * * ." ''All 
these proved to be nonpoisonous." 

3. "Azo-blue ib harmless, both when administered by the stomach and subcuta- 

neously." A. A dog received 237 milligrams per kilogram body weight, or 166 
grains per 100 pounds; 2 days later this same dose was repeated, and the urine 
was a violet color strongly alkaline and contained a little albumen. The next 
day the dose was increased to 2.5 times; colorless urine, and little albumen; 
there was no phenol. The next day 4 tiuie^ the original dose was administered; 
abundant bluish- violet urine and little albumen. No administration for 4 
days, when 2.5 times the original dose were given, and that dose repeated 3 days 
later; during this time the urine was colorless and contained little albumen; 
there was a very slight increase in weight. B. A dog received 319 milligrams 
per kilogram body weight, or 233 grains per 100 pounds daily for one month; 
animal remained well with good appetite; a slight amount of albumen made 
its appearance in the urine, {p. 144-) 



COMPILED DATA UNDEE GREEN TABLE ISTUMBEES. 113 

UNFAVORABLE. 

1. Weyl (p. 144)'- "A slight amount of albumen made its appearance in the urine." 

G. T. 394. 

Trade names. — Dinitrosoresorcin; Dark Green; Russian Green; 
Alsace Green; Fast Green O; Chlorin; Fast Myrtle Green. 
Scientific name. — Dinitroso-resorcinol (Dioximidoquinone) . 
Discovered and patented. — 1875. 
STiade. — Green. Not offered. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 63): '' According to the above experiments Dinitroso-resorcinol is not 

dangerous to dogs when administered by the stomach even in large doses; 
while hypodermic administration proves fatal within 24 hours, in the proportion 
of 190 milligrams per kilogram of body weight" (that is, 132 grains per 100 
pounds). 

3. A. A dog received 173 milligrams per kilogram body weight, or 121 grains per 100 

pounds; scanty dark-brown urine; the next day the same dose was repeated and 
urine continued dark brown, and contained trace of albumen as well as distinct 
reaction for iron; the next day the dose was repeated; animal remained lively; 
the day after that the dose was increased 50 per cent; no albumen. The loss in 
body weight was only 4 per cent. B. A dog received 198 milligrams per kilo- 
gram body weight, or 139 grains per 100 pounds; seems to have been loss of 
appetite, coupled with dark-brown, almost black urine; 2 days later the dose was 
doubled, and the urine was colored green by ferrous oxid, and contained no 
albumen nor sugar; 2 days later the dose was increased 50 per cent, and some 
albumen was then found in the urine, (p. 62.) 

G. T. 398. 

Trade name. — Naphthol Green B. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Naphthol Green; Naphthol Green B. 

Scientific name. — Ferrous sodium salt of nitroso-betanaphthol- 
beta-monosulphonic acid. 

Discovered. — 1883. 

Shade. — Green. Offered by 2 out of 12 sources. 

FAVORABLE. 

1. Weyl (p. 64): A. A dog received 172 milligrams per kilogram body weight, or 120 
grains per 100 pounds body-weight; the urine was greenish, and conjunctiva 
stained intensely green; dose was repeated 3 successive days, and the next day 
the dose was increased to fivefold; appetite undisturbed, and animal remained 
lively. B. A dog received 417 milligrams per kilogram body weight, or 292 
grains per 100 pounds; there was a dirty yellowish-green color to the urine; no 
albumen, and not more than traces of iron. The animal was normal within a 
day, and two days after the same dose was repeated; no change in animal was 
recorded, except that on the day following the feces were normal, but colored 
green. 

97291°— Bull. 147—12 8 



114 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

2. Weyl (p. 65): "Experiments 1 and 2, in which 2 to 5 grams of the color were intro- 

duced directly into the stomach, demonstrated its harmlessness in this method 
of administration." 

3. Buss lists it as nonpoisonous. 

UNFAVORABLE. 

1. Prohibited by Confectioners' List. 

2. Weyl (p. 65): "On the other hand, in a hypodermic administration, in two out of 

three cases abscesses and septic fever were induced." 

G. T. 399. 

Trade names. — Sun Yellow; Curcumin S; Jaune Soleil; Maize. 
Scientific name. — Sodium salt of the so-called Azoxy-stilbene-disul- 
phonic acid. 

Discovered. — 1883. 

Shade. — Yellow. Not offered. 

FAVORABLE. 

1. Meyer (/. Amer. Chem. Soc, 1907, v. 29, p. 897): A dog received 100 milligrams 
per kilogram body weight, or 70 grains per 100 pounds, increased geometrically 
through the fourth day, when diarrhea set in; up to this time the animal had 
been given 19.27 grams, or 1,465 milligrams per kilogram body weight, equiv- 
alent to 1,026 grains per 100 pounds body weight; the average dose per day 
would have been 366 milligrams per kilogram body weight, or 256 grains per 
100 pounds; the animal was given its fifth portion of coloring matter the same 
size as the fourth, thereupon color was omitted, and for the following 7 days the 
dosage of the third day, which amounted to 400 milligrams per kilogram body 
weight, or 280 grains per 100 pounds body weight, was given; the urine was col- 
ored orange throughout the entire test after the first day; the fecal matter also 
was of orange color; slight diarrhea on the fourth and twelfth days of the test, 
and vomiting on the fifth day, the cause of which does not seem to have been 
definitely determined; the autopsy revealed nothing abnormal. 

G. T. 425. 

Trade names. — Auramin; Auramin O; Pyoctanin Aureum. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Auramin O; Auramin; Canary Yellow. 

Scientific name. — Hydrochlorid of imido-tetramethyl-diamido- 
diphenylmethane. 

Discovered. — 1883. 

Shade. — Greenish yellow. Offered by 3 out of 12 sources. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Chlopin {p. 157): On his own experiments classes it as poisonous. The experi- 
mental data are as follows: 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 115 

Experimental data by Chlopin. 
[1 gram=69 ing=48 grains.] 

General condition of animal and urine. 



Dog quite normal; acid; no albumen. 

Urine strong brown yellow; traces of albumen; appetite less. 

Thin stool. 

Diarrhea; urine brown yellow, pales with sulphuric acid, and 

contains much albumen. 
Stool normal; color of urine weaker; much albumen; eats well; 

lively. 
Stool normal; urine less colored; less albumen. 
Stool normal; urine less colored; traces of albumen. 
Stool normal; urine less colored; insignificant traces of albumen. 
Do. 
Do. 
Strongly brown yellow; much albumen. 
Dog depressed; lies down; eats little. 
Vomits and diarrhea; urine strong yellow; little albumen; 

takes only milk. 
Vomits and diarrhea; urine strong yellow; much albumen. 
Feces normal color; color urine almost normal; much albumen. 
Feces normal color; color urine almost normal; albumen less. 
Do. 



Date. 


Dose. 


Weight. 


24-hours' 
urine. 


1901. 
Mar. 2-4 
6 


Grams. 
1.0 


Kilos. 
14.4 


cc. 
550 
340 


7 






8 








9 








10 








11 






335 


12 






13 








14 


2.0 


13.2 




15 




16 







None. 
295 

480 


17 






19 






20 






21 






352 
380 


24 


10.4 


13.6 



1 Subcutaneously. 
DOUBTFUL. 



1. WiNOGRADOw {Zts. Nohr. Genussm., 1903, v. 6, p. 589) says it noticeably retarda 
digestive action; is not indifferent. 

G. T. 427. 

Trade names. — Malachite Green; New Green; Fast Green; Benzal 
Green; Diamond Green B; Malachite Green B; New Victoria Green; 
Vert Diamant; Bitter-almond-oil Green. 

Names under which it was offered on the United States marJcet as a 
food color in 1907. — Green M; New Green Crystals; Green 088. 

Scientific name. — Zuic double-chlorid, oxalate, ferric double-chlorid 
of tetramethyldi-para-amido-triphenyl-carbinol. 

Discovered. — 1877-78. 

Shade. — Bluish green. Offered by 2 out of 12 sources. 



Malachite Green are (is) 



FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl {p. 24)'. * 'According to Grandhomme * * 

also nonpoisonous." 

3 <« ^ •jt -x- Malachite Green are (is) as is now established, almost without poison- 
ous action." {p. 55.) 

4. Lewln (Lehrbuch der ToxiJcologie, 1897, p. 231) says when free from arsenic it is 

harmless. 

5. Buss lists it as nonpoisonous. 

unfavorable. 

1. Penzoldt (Archiv. exper. path, pharm., 1890, v. 26, p. 312): One hundred milli- 
grams per kilogram body weight of rabbit, or 70 grains per 100 pounds, injected 
subcutaneously, caused after the third day motor paralysis and occasional 
cramps, which resulted fatally at the end of the ninth day. 



116 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



2. Lewin {Lehrhuch der Toxikologie, 1897, p. 231): In the case of one workman, in 
contrast with others who had long been unaffected by this substance, itching, 
burning, inflammation, and swelling of hands and feet, and formation.of blisters 
occurred. 

G. T. 428. 

Trade names. — Brilliant Green; New Victoria Green; Emerald 
Green; Malachite Green B; Ethyl Green; Fast Green J. 

Names under wliicli it was offered on tlie United States marlcet as a 
food color in 1907. — Green E; Green 087; Emerald Green Crystals. 

Scientific name. — Sulphate of zinc-double-chlorid (rarely oxalate) 
of tetraethyl-diamido-triphenyl-carbinol. 

Discovered.— 1^1 ^-^0, 

Shade. — Yellowish green. Offered by 3 out of 12 sources. 

FAVORABLE. 



1. Lewin {Lehrhuch der Toxikologie, 1897, p. 

harmless. 

2. Buss lists it as nonpoisonous. 



') says when free from arsenic it is 



UNFAVORABLE . 

1. Chlopin {pp. 171-2): Classifies it as ''very poisonous" on his own experiments 
(see p. 181). The experimental data are as follows: 

Experimental data hy Chlopin. 

No.l. 

[1 grain=125 mg=87.5 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
iirine. 


General condition of animal and urine. 


1901. 
Apr. 24 

25 


Grams. 


Kilos. 

8 


cc. 

410 


Before experiment dog is well; urine normal. 


2 


Soon after giving dye vomiting and diarrhea; in the evening 

only drank water; vomiting kept up. 
No vomiting; urine greenish; acid; insignificant traces of 


26 




395 


27 






albumen. 
Do. 


28 


2 




400 


No vomiting; urine greenish; acid; no albiunen. 


29 




Do. 


30 






395 


Do. 


May 1 
2 






Urine normal; dog quite well. 








Do. 


3 






3^5 


Do. 










Total.... 


4 





No. 2. 

(1 gram=lll mg=78 grains.) 



1902. 
Jan. 21 

23-24 
25 
26 

Total.... 



3 


9 


400 


2 


7.2 










5 



Before experiment dog quite normal; uruie normal; after giv- 
ing dye very violent vomiting several times. 
Urine gi-eenish in color; acid; very much albumen; no vomiting. 

Do. 
Died during the night. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 

Experimental data by Chlopin — Continned. 

No. 3. 

[1 gram=119 mg=83 grains.] 



117 



Date. 


Dose. 


Weight 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Jan. 28 

29 


Grams. 
3 

2 


Kilos. 
8.4 


cc. 
370 


Before experiment dog and urine normal; soon after giving dye 

vomiting began, lasting over an hour; dog stands with 

difficulty. 
During night dog improved somewhat, began to eat; drinks 

much; soon after giving dye vomiting. 
During night vomiting and diarrhea; during night 30th, 31st, 

in bad condition; does not take food. 
During night 31st second dog found dead in cage. Cause of 

death, "paralysis of the heart. " 


30 






31 
















Total.... 


5 





2. Lewin {Lehrhuch der Toxikologie, 1S97, p. 231): In the case of one workman, in 
contrast with others who had long been unaffected by this substance, itching, 
burning, inflammation and swelling of hands and feet, and formation of blisters 
occurred. 

G. T. 433. 

Trade name. — Guinea Green. 

Name under wJiicJi it was offered on the United States marlcet as a 
food color in 1907. — Guinea Green B. 

Scientific name. — Sodium salt of diethyldibenzyl-diamido-tri- 
phenyl-carbinol-disulphonic acid. 

Discovered. — 1883. 

Shade. — Green. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Chlopin (p. 174): On his own experiments classified it as "nonpoisonous. " The 
experimental data are as follows : 

Experimental data by Chlopin. 
[1 gram=200 mg=140 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 18 
19 


Grams. 
2 


Kilos. 
5 


cc. 

250 
235 
280 
290 
270 
270 
260 
240 
290 
246 


Dog and urine normal before experiment. 

Urine slightly greenish, no albumen; vomited at night. 

No vomiting. 


20 






21 






Urine sUghtly greenish; no albumen. 


22 






Urine normal in color and composition. 


23 






Do. 


24 


2 




Do. 


25 




Do. 


26 


2 




Do. 


27 




Do. 


28 


2 




Do. 


29 




243 
233 
230 


Do. 


30 


' 




Do. 


31 




Do. 










Total . 


10 





G. T. 434. 

Trade names. — Light Green SF bluish; Acid Green. 
Scientific name. — Sodium salt of dimethyldibenzyl-diamido-tri- 
phenyl-carbinol-trisulphonic acid. 



118 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



Discovered. — 1879. 

Shade. — Green. Offered by 1 out of 12 sources. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin (pp. 176-7): Examined this color, and on his own experiments classes 
it as "nonpoisonous, but not entirely indifferent." The experimental data 
are as follows: 

Experimental data by Chlopin. 

No. 1. 
[1 gram=133 mg=93 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Apr. 24 


Grams. 
2 


Kilos. 

7.5 


cc. 
380 


Dog and urine normal. 

Urine green; acid; no albumen. 


26 






347 
297 


Urine green: traces of albumen. 


27 






Do. 


28 


2 




Do. 


29 






Urine green; no albumen. 


30 






360 


Urine less green; no albumen. 


31 






Do. 


May 1-3 








Do. 






370 


Do. 










Total . 


4 





No. 2. 
[1 gram=110 mg=77 grains.] 



1902. 
Aug. 5 


3 


9.1 


300 
310 


Dog and urine normal. 

Urine greenish, acid, no albumen. 


7 


3 
3 
3 
3 




Do. 


8 




320 
350 


Do. 


9 




Do. 


10 




Do. 


11 




400 
350 


Do. 


12 




9 


Do. 








Total . 


15 





DOUBTFUL. 



1. WiNOGRADOw (Zts. Nahr. Genussm. 1903, v. 6, p. 589) says it noticeably retards 
digestive action; is not indifferent. 

G. T. 435. 

Trade names. — Light Green SF yellowish ; Acid Green ; Acid Green 
extra cone. 

Names under which it was offered on the United States market as a 
food color in 1907. — Acid Green cone. V N; Light Green SF yellow 
shade ; Acid Green cone. 780 ; Pistacliio. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 119 

Scientific name. — Sodium salt of diethyldibenzyl-diamido-tri- 
phenyl-carbinol-trisulphonic acid. 
Discovered. — 1879. 
Shade. — Green. Offered by 4 out of 12 sources. 

FAVORABLE. 

1. LiEBER {p. 144): The animal was a fully developed male guinea pig, and received 
per kilogram body weight 240 milligrams, or 168 grains per 100 pounds, five 
times in all, every other day. There was apparently nothing irregular or ab- 
normal observed during the whole test of nine days. 

G. T. 448. 

Trade nannes. — Magenta; Fuchsin; Roseiii; Anilin Red. 

Obsolete Thames. — Rubin; SoKerino; Fuchsiacin; Rubianite; Azalein; 
Ery throbenzin ; Harmalin. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Magenta powder A; Fuchsin Crystals; Magenta 
FABSRed 101. 

Scientific name. — Mixture of hydrochlorid or acetate of pararo- 
sanilin (triamidotriphenylcarbinol) and rosanilin (triamidodiphenyl- 
tolylcarbinol) . 

Shade. — Bluish-red. Offered by 4 out of 12 sources. 

FAVORABLE, 

1. Permitted by Confectioners' List. 

2. Weyl {-p. 22): "The colors examined * * * Fuchsin were (was) found to be 

nonpoisonous; " "Similarly a hen which had eaten for three weeks oats covered 
with fuchsin was in good health." {p. 24-) 

3. "According to Grandhomme rabbits bear without injury fuchsin free from arsenic 

* * *." {p. 31.) 

4. "Fuchsin * * * (is) as is now established, almost without poisonous action." 

(p. 55.) 

5. Fraenkel {p. 574), quoting Penzoldt, says that it is entirely nonpoisonous, and 

completely prevents putrefaction. 

6. Permitted by the law of Austria. 

7. Lewin {Lehrbuch der Toxikologie, 1897, p. 230), says when free from arsenic it is 

harmless. 

8. Clouet and Bergeron ( /. pharm. chim., 1871, v. 25, p. 296): One of them took 

personally 500 milligrams, that is, 7.7 grains in 16 days; there was no digestive 
disturbance of any kind, and the urine, which was examined daily, contained 
no albumen. They cite a case of Bright's disease, in which the amount of 
albumen decreased when fuchsin was administered, and they conclude that 
fuchsin may be good for sufferers from Bright's disease. 

unfavorable. 

1. Forbidden by the law of France. (See Lieber, p. 31.) 

2. Chlopin {p. 178): Examined this color, and on his own experiments classes it as 

"Suspicious because of vomiting and traces of albumen." The experimental 
data are as follows: 



120 



COAL-TAR COLORS USED IF FOOD PRODUCTS. 

Experimental data by Chlopin. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 18 

19 


Grams. 
3 


Kilos. 


cc. 
270 

280 


Dog before experiment well and urine normal; vomited several 




times after receiving dye. 
Urine quite red; acid: no albumen: general condition normal. 


20 






Do. 


21 


2 




320 


Urine less colored; acid; no albumen; vomited once. 


22 




Urine darkish; acid; traces alDumen. 


23 








Color normal; no albumen. 


24 








Do. 












Total . 


5 





Note.— This sample may have contained some phosphin, G. T. 532, see page 133. 

DOUBTFUL. 

1. WiNOGRADOW (Zts. Nahr. Genussm. 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 450, 

Trade names. — Hofmann Violet; Dahlia; Red Violet 5E, extra; 
Violet R; lodin Violet; Primula; Violet 5 R; Violet R R. 

Scientific name. — Mixture of the hydrochlorids or acetates of the 
monodi- or trimethyl- (or ethyl-) rosanilins and pararosanilins. 

Discovered. — 1863. 

Shade. — Violet. Not offered. 

FAVORABLE. 

1. Weyl(p.^-^): "^ * * Anilin Violet (Dahlia) * * * (is)alsononpoisonous." 

2, Buss lists it as nonpoisonous. 

UNFAVORABLE. 

1. Fraenkel (p. 574) quotes Penzoldt, and says it completely arrests development, 
and causes muscular paralysis. 

G. T. 451. 

Trade names. — Methyl Violet B; Direct Violet; Dahlia; Paris 
Violet; Violet de Methylanilin ; Pyoctanin. 

Names under wJiicJi it was offered on the United States marlcet as a 
food color in 1 907 .—Methjl Violet; Methyl Violet B; Methyl Violet 
BB extra; Methyl Violet 3 B D. 

Scientific name. — Hydrochlorid of penta- and hexamethyl- para- 
rosanilin. 

Discovered. — 1861. 

Shade. — Violet. Offered by 5 out of 12 sources. 



FAVORABLE. 



1. Permitted by Confectioners' List. 

2. Permitted by the Austrian law. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 121 

3. Weyl (p. U): " * * * Anilin Violet (Dahlia) * * * [is] also non^ 

poisonous." 
4_ << * * vr 3^/[ethyl Violet [is] as is now established, without poisonous action."' 

{p. 55). 

5. Fraenkel (/), 575): ''Methyl Violet * * * is relatively nonpoisonous." 

6. Buss lists it as nonpoisonous. 

UNFAVORABLE. 

1. Graefe and Braunschweig {Fortschr. Medizin, 1890, v. 8, p. 405): "It seems 

to be proven that damage will actually result even in the case of most cautioua 
use, which we are sure we exercised." 

2. Santori ( MoleschoW s Untersuchungen, 1895, v. 15, p. 52): I. A dog weighing 

7,600 grams received 5.6 grams dye in 12 days; this amounts to 61 milligrams 
per kilo per day, or 43 grains per 100 pounds per day. Continued vomiting 
beginning with 0.1 gram dye; progressive emaciation and general falling away,^ 
catarrh of eyes and nose; distinct dislike for food and great desire to sleep,' 
temperature below normal, urine unchanged. Loss of weight 1,600 grams, or 
21 per cent. The animal died on the thirteenth day. The autopsy showed a 
pale and blood-poor liver; the kidneys were in a typically congested condition 
and contained accumulations of blood corpuscles. II. A second dog weighing 
6,000 grams received 3.8 grams dye in 14 days, which amounts to 71.4 milli- 
grams per kilo per day, or 50 grains per 100 pounds per day. The animal died 
on the fourteenth day. There was daily vomiting and rapid emaciation; final 
weight loss was 1,100 grams, or 18.3 per cent; temperature normal; bloody 
urine beginning the eighth day. The autopsy showed a blood-poor liver, soft 
and swollen epithelia; kidneys the same as in the case of the preceding dog. 

G. T. 457. 

Trade names. — Anilin Blue, spirit-soluble ; Spirit Blue ; Fine Blue ; 
Bleu Lumi ere ; Opal Blue; Gentian Blue 6B; Hessian Blue; Bleu-de- 
Nuit. 

Scientific name. — Hydrochlorid sulphate or acetate of triphenylro- 
sanilin and triphenylpararosanilin. 

Discovered.— 1860-1862. 

Shade. — Greenish blue; not offered. 

favorable. 

1. Permitted by Confectioners' List. 

2. Santori {MoleschoWs Untersuchungen, 1895, v. 15, p. 48) says it is harmless. 

A dog weighing 4,500 grams received 17 grams dye in 30 days, which amounts to 
126 milligrams per kilo per day or 88 grains per 100 pounds per day. Weight 
remained the same, general condition good, urine and temperature unchanged; 
killed by chloroform; autopsy showed everything normal. 

3. LiEBER {p. 14-), where it is stated to be permitted by the Austrian law {pp. 22-23), 

where it is stated to be permitted by the Italian law (p. 31), where it is stated 
to be permitted by the French law in candies, pastilles, sweetmeats, sauces, 
fruits, and certain liqueurs ordinarily not colored. 

4. Weyl {p. 22), quoting Sonnenkalb (p. 24), quoting Grandhomme. 

5. Fraenkel {p. 580) states that it is effective in only 5 per cent of malaria cases. 

6. Permitted by the law of Austria. 

7. Buss lists it as nonpoisonous. 



.122 



COAL-TAK COLOES USED IN FOOD PEODUCTS. 



UNFAVORABLE. 

1. Weyl {p. 23), quoting Friedrich, where poisoning was produced in a young man 
engaged in packing this dye. 

G. T. 459. 

Trade names. — lodin Green; Pomona Green; Night Green; Vert 
Lumiere. 

Scientific name. — Zinc-double-chlorid of heptamethyl-rosanilin- 
chlorid. 

Discovered and patented. — 1866. 

STiade. — Green. Not offered. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin (p. 175) on his own experiments classes it as "suspicious." (See p. 181). 
The experimental data are as follows : 

Experimental data hy Chlopin. 

[1 gram=167 ing=H7 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 9 
10 


Grams. 
6 


Kilos. 
6 


cc. 
420 
470 
441 
420 
390 
400 
442 
370 


Before experiment dog and urine normal. 
Do. 


11 






Urine slightly greenish; no albumen. 
Do. 


12 


2 




13 




Urine has greenish opalescence; traces of albumen. 
Do. 


14 






15 






Urine has greenish opalescence; no albumen. 
Do. 


16 


2 




17 




Urine has greenish opalescence; traces of albiunen. 


18 






400 


Normal color; no albumen. 










Total.. 


G 





2. Buss lists it as poisonous. 



DOUBTFUL. 



1. WiNOGRADow {Zts. Nahr. Genussm., 1903, v. 6, p. 589) says it noticeably retards 
digestive action; is not indifferent. 

G. T. 462. 



Trade names. — Acid Maganta; Acid Fuchsin; Acid Rubin; Fuch- 
sin wS; Acid Rosein; Rubin S. 

Names under which it was offered on the United States marlcet as a 
food color in 1907. — Acid Magenta Powdered; Acid Magenta. 

Scientific name. — Mixture of the sodium or ammonium salts of the 
trisulphonic acids of rosanilin and pararosanilin. 

Discovered. — 1877. 

Shade. — Red. Offered by 2 out of 12 sources. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



123 



FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Cazeneuve {Arch. gen. med., 1886, p. 753) says it may be taken without effect by 

man and animals, sick or well, in large doses. 

3. Weyl (p. 55), where he says that it is established of this color that it is almost with- 

out poisonous action. 
2. LiEBER {jp. 14), where it is stated to be permitted by the law of Austria {p. 31), 
where it is stated to be permitted by the law of France for confectionery, cor- 
dials, and the like. 

5. Permitted by the law of Austria. 

6. Permitted by the law of Italy. 

7. Cazeneuve and Lepine {Compt. rend., 1885, v. 101, p. 1011): A. Dog: 15 kilos 

weight, received — 



Days. 


Grams. 


Milligrams 
per kilo. 


Grains per 
100 pounds. 


15 
5 

5 
5 


1 
2 
5 
10 


67 
134 
335 

670 


47 
94 
235 
470 



No diarrhea; no vomiting; no albuminuria; urine colored only occasionally, 
but did contain the leuco compound of the dye. B. Man: 1. Afflicted with 
Bright' 8 disease; took two grams daily for one week; no effect. 2. Afliicted 
with renal cirrhosis; four grams daily for several days; no effect. 3. A well 
man took four grams daily for several days; no effect. 
8. Cazeneuve and Lepine (Bull, de Vacad. de med. 1886, p. 643): Tolerated by man, 
sick or well. 

G. T. 467. 

Trade name. — Acid Violet 6B. 

Scientific name. — Sodium salt of dimethyl diethyl dibenzyl triamido 
triphenyl carbinol disulphonic acid. 
Discovered and patented. — 1889. 
SJiade. — Violet. Not offered. 

FAVORABLE. 

1. Santori {MoleschotV s Untersuchungen, 1895, v. 15, p. 54): A dog weighing 4,250 
grams received 12.5 grams dye in 28 days, which amounts to 105 milligrams per 
kilo per day, or 74 grains per 100 pounds per day. The dog vomited the color 
only two or three times and was otherwise normal. Appetite, temperature, 
and urine all remained normal. Conclusion: Nonpoisonous; autopsy also 
showed everything normal. 



Nothing. 



UNFAVORABLE. 

G. T. 477. 



Trade names. — AlkaH Blue; Nicholson Blue; Fast Blue. 

Scientific name. — Mixture of sodium salts of triphenyl rosanilin 
monosulphonic acid and of triphenyl para rosani 1 i n-monosulphonic 
acid. 



124 



COAL-TAE COLORS USED IN POOD PRODUCTS. 



Discovered and patented. — 1862. 
Shade. — Blue. Not offered. 

FAVORABLE. 

L. Santori {Moleschotfs Untersuchungen, 1895, v. 15, p. 45): A dog weighing 4,500 
grams received 25 grams dye in 30 days, which amounts to 185 milligrams per 
kilo per day, or 129.5 grains per 100 pounds per day. The urine remained of 
normal color, but the stool was a deep blue black. Throughout the whole time 
the animal was in perfect health. Killed with chloroform; autopsy showed 
everything normal. 

UNFAVORABLE. 

Nothing. 



G. T. 478. 



Trade names. — Bavarian Blue DSF; Methyl Blue, water-soluble; 
Navy Blue B; Methyl Blue for silk MLB. 

Scientific name. — Sodium, salt of triphenyl pararosanihn di- and 
tri-sulpho acid. 

Discovered. — 1862; not patented. 

Shade. — Blue. Not offered. 



Nothing. 



FAVORABLE, 



UNFAVORABLE. 



1. Chlopin (p. 170) examined this color, and on his own experiments classed it as 
"nonpoisonous but not quite indifferent." 

Experimental data by Chlopin. 
[1 grain=115 ing=81 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 18 
19 


Grams. 
2 


Kilos. 

8.7 


cc. 
450 
365 
380 
370 


Dog and urine quite normal. 
Urine slightly greenish; no albumen; acid. 
Do. 


23 






24 


2 




Do. 


25 




Do. 


26 


2 






Do. 


27 




370 
320 


Do. 


28 


2 




Do. 


29 




Do. 


30 


2 






Urine slightly greenish; traces of albumen; acid. 
Do. 


31 




525 


June 1 






Do. 


2 






327 


Do. 


3 






Do. 


4 


3 


! 


Do. 


5 


1 


Urine slightly greenish; traces of albumen; acid; diarrhea. 
Do. 


6 


3 




405 


7 




Urine slightly greenish; traces of albumen; acid. 
Do. 


8 


3 




395 
353 
370 
340 
1400 
425 


9 




Do 


10 


3 




Do. 


11-15 




Color normal' traces of albumen 


16 






Do. 


17-29 




8.5 


Do 








Total . 


22 





1 DaiLv. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



125 



G. T. 479. 

Trade names. — Methyl Blue O; Brilliant Cotton Blue greenish; 
XL Soluble Blue; Diphenylamin Blue; Bavarian Blue DBF; Soluble 
Blue 8B and lOB; Helveria Blue. 

Scientific name. — Sodium salt of triphenyl-pararosanilin tri- 
sulphonic acid. 

Discovered and patented. — 1862. 

Shade. — Blue. Not offered. 



Nothing. 



FAVORABLE. 



UNFAVORABLE, 



1. Chlopin {p. 168) examined this color and on his own experiments classed it as 
"suspicious" or "nonsuspicious" dependent upon the make of goods. 

Experimental data by Chlopin. 

No. 1. 

[1 grain=75 iiig=52 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and. mine. 


1901. 
May 14 
15 


Grams. 
2 


Kilos. 
13.4 


cc. 
460 


Dog normal; no albumen. 

Color chocolate-brown; insignificant traces of albumen. 


16 


2 






Color same; no albumen. 


17 




410 


Urine normal; no albumen; dog is well. 










Total.. 


4 





No. 2. 
[1 gram=152 mg. = 106 grains. 



1901. 
Nov. 12 
13 


3 


6.G 


300 


15 


3 
3 
3 
3 






16 




360 
305 
330 


17 




19 




20 




21 








22 




6.8 










Total.. 


15 



Dog quite well; urine normal color; acid; no albumen. 

Do. 

Do. 

Do. 
Urine scarcely perceptible greenish sheen; acid; no albvunen. 
Urine greenish color; no albumen. 
Urine darker; no albimien. 
Urine color normal; no albumen. 
Color almost normal. 



This preparation from Moscow; not suspicious. 

No. 3 (Merck's Preparation). 
[1 grani= 147 mg= 103 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1903. 
J'eb. 18 

19 


3 

3 

3 

3 
3 


0.9 


400 


Before experiment dog quite normal; urine acid; no albumen; 

nornial yellow color; 2 hom's after giving dye vomiting. 
Vomiting stopped; diarrhea; urine chocolate-brown; reaction 

acid; considerable albumen; appetite not decreased. 
During night diarrhea; no vomiting; urine brown; acid; traces of 

albumen; without acid urine becomes blue. 
No diarrhea; no vomiting; urine brown; traces of albumen. 
Urine broAvn, mth blue sheen* traces of albumen. 


20 




330 


21 




22 


6.8 




23 




Urine blue chocolate-brown; otherA\'ise normal. Urine acquired 
usual color 8 days later. 










Total.. 


15 



Conclusion : ' ' Suspicious . 



126 COAL-TAR COLOES USED IN FOOD PRODUCTS. 

G. T. 480. 

Trade names, — Soluble Blue; China Blue; Cotton Blue; Bleu 
Marine; Water Blue; Water Blue 6 B extra; London Blue extra. 

Names under which it was offered on the United States marJcet as a 
food color in 1907. — Pure Soluble Blue. 

Scientific name. — Sodium, ammonium or calcium salt of the tri- 
sulphonic acid (with some disulphonic acid) of triphenyl-rosanilin and 
triphenyl-pararosanilin. 

Discovered and ^patented. — 1862. 

Shade. — Blue. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Permitted by law of Austria. 

2. LiEBER {jp. 147): A guinea pig received 306 milligrams per kilogram body weighty 

or 214 grains per 100 pounds, once a day seven times every other day; the weight 
remained substantially constant, a slight gain of less than f per cent being noted. 
"Nothing irregular or disturbing whatsoever was observed during the whole 
period. " 

3. Santori {Moleschott's Untersuchungen, 1895, v. 15, p. 45): A dog weighing 4,500 

grams received 30 grams dye in 30 days which amounts to 223 milligrams per 
kilo per day or 156 grains per 100 pounds per day. Animal remained well 
throughout; no loss of weight or appetite; urine normal color, stool deep blue; 
killed with chloroform; autopsy showed a pea-green coloring of the cortex of 
the kidneys, 

UNFAVORABLE. 

1. Fraenkel (p. 574), quoting Penzoldt, says that it completely arrests germ devel- 

opment, and causes changes internally. 

2. Santori {Moleschott's Untersuchungen, 1895, v. 15, p. 46): Regards this as injurious 

hypodermically, but not through mouth. A dog weighing 4,000 grams received 
3.5 grams of dye hypodermically in 16 days, at the end of which time he died; 
this amounts to 55 milligrams per kilo per day or 38.5 grains per 100 pounds 
per day. The autopsy showed the liver to be free from blood; kidneys soft 
and congested; all organs swollen and colored. 

G. T. 483. 

Trade names. — Aurin; Kosolic Acid; Yellow Corallin. 
Scientific name. — Mixture of aurin (trioxytriphenyl-carbinol) oxi- 
dized aurin, methylaurin, and pseudo-rosolic acid (corallin phthalin). 
Discovered. — 1834. 
Shade. — Yellowish brown. Not offered. 

FAVORABLE. 

1. Lewin (Lehrbuch der Toxikologie, 1897, p. 231): Rosolic Acid is positively non- 
poisonous. 



COMPILED DATA UNDER GEEEN TABLE NUMBEES. 



127 



UNFAVORABLE. 



1. Chlopin {p. 167) examined this color, and on his own experiments classes it 
''strongly poisonous." The experimental data are as follows: 

[1 gram=137 nig=96 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Mar. 12 

13 


Grams. 
1 

2 
3 
3 


Kilos. 
7.3 


cc. 
330 

375 
300 


Before experiment dog quite well; urine normal color; acid; no 

albumen. 
Diarrhea; urine faint red. 


14 




Diarrhea; lassitude; eats little; urine red; no albiomen. 


15 




Violent diarrhea and vomiting; dog stands on feet with diffi- 
culty; eats nothing. 

Same conditions as on preceding day; dog sick for a long time 
after. 


16 














Total- 


9 



2. Prohibited by the German law of 1887. 

3. Prohibited by the Belgian law of June 17, 1891. 

4. Buss lists it as poisonous. 

DOUBTFUL. 



1. Lewin {Lehrbuch der Toxikologie, 1897, p. 231): Rosolic Acid is positively non- 
poisonous. Small animals can take 1 gram and more of it. In Austria it is 
prohibited for use in coloring foods. Corallins, or red (Pseonin) or yellow 
colors, consisting of Aurin and Rosolic Acid were regarded as poisonous 
because in experiments on man and animals illness occurred, but are said to 
be poisonous only in the presence of arsenic, phenol, or anilin. These sub 
stances are prohibited in the coloring of food. 

G. T. 488 or 490. 

Trade name. — Victoria Blue; Victoria Blue B; Victoria Blue 411. 
Scientific na^mes. — Hydrochlorid of phenyltetra (pent a) methyl- 
triamido-diphenyl-alpha-naphthyl-carbiiiol (note: 4R is bracketed). 
Discovered and patented. — 1883. 
Shade. — Blue. Not offered. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Santori {MoleschotVs Untersuchungen, 1895, v. 15, p. 47): A dog weighing 5,250 
grams received 10.5 grams dye in 22 days, which amounts to 45 milligrams 
per kilo per day or 32 grains per 100 pounds per day. After receiving 1.5 
grams the animal suffered copious continuous salivation, anemia, and emacia- 
tion and occasional vomiting. The urine's color did not change; the feces 
became blue; temperature slightly above and below normal; although highly 
emaciated (loss in weight was 1,750 grams or 33J per cent) the animal retained 
its appetite; animal died on the morning of the 23d day. The autopsy showed 
oesophagus, stomach, and intestines colored deep blue and filled with a green- 
ish scum, extended and strong catarrh of the stomach and intestines; kidneys 
and liver contained very little blood. Conclusion: Poisonous. 
(Note: It is uncertain which of these two dyes Santori used.) 



128 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 

G. T. 502. 



Trade name. — Ehodamin G and G extra. 
Scientific name. — Chiefly Trie thy Irhodamin. 
Discovered and patented. — 1891. 
Shade. — Bluish. Offered by 2 out of 12 sources. 



Nothino;. 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin (p. 184) examined this color, and on his own experiments classes it as 
* ' suspicious . " The experimental data are as follows : 

Experimental data by Chlopin. 
ri gram= 167 ing= 117 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1903. 
Feb. 18 

19 


Grams. 
3 

3 
3 
3 
3 


Kilos. 
6 


cc. 
310 


Dog normal; urine acid; no albumen; after 2 hours thin stool; 

remainder of day lively; good appetite. 
Urine fuchsin color, acid, no albumen; stool and appetite normal. 
Goes to stool without results* otherwise as above 


20 






21 




270 
320 


Do. 


22 




Do 


23 




Goes to stool without results; urine normal after 8 days. 










Total.. 


15 





G. T. 504. 

Trade names. — Rhodamin B; Rhodaniin O; SafraniliTi. 

Names under wliicJi it was offered on the United States marlcet as a 
food color in 1907. — Rhodamin B extra; Rhodarain; Rhodarain B. 

ScientiHc name. — Hydrochlorid of diethylmeta-amido-phenol- 
phthalein. 

Discovered and patented. — 1887. 

Shade. — Bluish red. Offered by 5 out of 12 sources. 

favorable. 

1. LiEBER (p. 141)'- A young female rabbit received 339 milligram body weight, or 
237 grains per 100 pounds, five times on alternate days. "During the whole 
period the animal seemed to be perfectly at ease, was lively, displayed good 
appetite, and gained steadily * * * ." The gain in weight was, roughly, 
7 per cent. 

UNFAVORABLE. 

1. Chlopin {pp. 182, 183) examined this color, and on his own experiments classifies 
it as "not poisonous, but not entirely indifferent; suspicious." The experi- 
mental data are as follows: 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 

Experimental data by Chlopin. 
f 1 gram = 109 mg = 76 grains.] 



129 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


Jeneral condition of animal and urine. 


1904. 
Feb. 18 

19 


Grams. 
3 

3 

3 
3 
3 


Kilos. 
9.2 


cc. 

420 

400 
400 


Dog normal; urine acid, no albumen; strong yellow color, 2 

hours alter giving color thin stool. 
Urine colored wine red, strong fluorescence, disappears on boii- 


20 




ing, and reappears on cooling; no albumen. 
Thin stool; no change in other respects. 


21 




No diarrhea; no change in other respects. 


22 




420 


General condition good; urine red and acid; no albumen. 








Total.. 


15 





Dog recovers. 



G. T. 512. 



Trade names. — Eosin; Eosin A; Eosiii B; Eosin A extra; Eosin 
Yellowish; Eosin G G F; Water-soluble Eosin; Eosin 3 J and 4 J 
extra. 

Names under wJiicJi it was offered on the United States marlcet as a 
food color in 1907. — Erythrosin I N; Eosin J; Eosin Y. 

Scientific name. — Alkali salts of Tetra-bromo-fluorescein. 

Discovered. — 1874. 

Shade. — Yellowish red. Offered by 3 out of 12 sources. 



FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Weyl (p. 5i): "According to Grandhomme, rabbits bear without injury * * * 

Eosin * * *." 

3. Permitted by the laAV of Austria. 

4. Buss lists it as nonpoisonous. 

UNFAVORABLE. 

1. Lewin (Lehrbuch der Toxikologie, 1897, p. 231): "The continued use of these 

coloring matters, as well as of Phenolphthalein, which becomes colored in the 
system, I regard as harmful, and, in fact, through action as coloring matters." 

2. Forbidden by the Italian law. 

G. T. 516. 

Tradenames. — Erythrosin G; PyrosinJ; Jaune d' Orient; Dianthici 
G; lodeosin G. 

"Name under which it was offered on the United States marlcet as a food 
color in 1907. — Er^-throsin yellowish shade. 

Scientific name. — Sodium or potassium salt of diiodofluorespein. 
97291°— Bull. 147—12 9 



130 



COAL-TAK COLORS USED IN FOOD PRODUCTS. 



Discovered. — 1875. 

SJiade. — Yellowish red. Offered bv 1 out of 12 sources. 



Nothino:. 



FAVORABLE. 



UNFAVORABLE. 



1. Chloptn {p. 181): Examined this color, and on his own experiments reports it as 
"injurious because of light albuminuria, vomiting, and diarrhea." The 
experimental data are as follows: 



Experimental data by Chlopin. 

No. 1. 
[1 gram = 156 mg = 109 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of aniuiai and urine. 


1901. 
Apr. 24 
25 


Grams. 
2 


Kilos. 
6.4 


cc. 
360 
353 
368 
370 


Before experiment dog and urine normal. 
Urine red yellow with greenish sheen; acid; no albumen. 
Urine red yellow with greenish sheen; acid; trace of albumen. 
Do 


26 






27 






28 


2 




Urine red yellow with greenish sheen; acid; no albumen. 


29 




355 
365 
365 


Do. 


30 






Do. 


May 3 






Do. 










Total . 


* 





No. 2. 

[1 gram = 152 mg = 106 grains.) 



1901. 

Nov. 24 




6.6 


345 


25 


3 
3 
3 
3 

3 


26 






27 






28 




380 
340 


29 




30 





Dec. 2-3 
















Total . 


15 



Dog and urine normal. 

Do. 
Urine fluorescent orange; no albumen. 
Vomiting, diarrhea; urine orange; no albumen. 
No vomiting and no diarrhea; urine fluorescent, red; no albu- 
men. 

Do. 

Do. 
Color and composition of urine norma!; dog well. 



DOUBTFUL. 

1. WiNOGRADOW {Zts. Ntthv . Genussm . 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 517. 



Trade names. — Erythrosin; Erythrosin B; lodeosin B; Eosin J; 
Eiyth rosin D; Pyrosin B; Eosin Bluish. 

Names under wliich it was offered on the United States marlcet as a 
food color in 1907. — Erythrosin Yellow Shade; Erythrosin B; Ery- 
throsin. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 131 

Scientific imme.— Sodium or potassium salt of tetraiodofluoresceiiL 

Discovered . — 1876. 

Shade. — Bluish red. Offered by 5 out of 12 sources. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

2. W'EYh (p. 31): ''According to Grandhomme, rabbits bear without injury * * * 

Erythrosine * ^ *." 

3. Permitted by the laAvs of France. 

4. Permitted by the law of Austria. 

5. Fraenkel (p. 574)'- ''Rose Bengal * * * produces no noticeable disturb- 

ances." 

6. Buss lists it as iionpoisonous. 

UNFAVORABLE. 

1. Lewin (Lehrbuch der Toxihologic, 1897, p. 231): "The continued use of these 
coloring matters, as well as of phenolphthalein, which becomes colored in the 
system, I regard as harmful, and, in fact, through action as coloring mat^'ers." 

G. T. 520. 

Trade names. — Rose Bengal; Rose Bengal A T; Rose Bengal N; 
Rose Bengal G. 

Names under wlncli it was offered on the United States marlcet as a 
food color in 1907. — Rose Bengal B; Phloxin B. 

Scientific name. — Alkaline salt of tetraiododiclilorofluorescein. 

Discovered. — 1875. 

Shade. — Bluish red. Offered by 2 out of 12 sources. 

favorable. 
1. Permitted by Confectioners' List. 

G. T. 521. 

Trade names. — Phloxin; Phloxin TA; Eosin lOB. 

Scientific name. — Sodium salt of tetrabromotetrachlorofluorescein. 

Discovered. — 1882. 

Shade. — Red. Not offered. 

favorable. 

1. Permitted by Confectioners' List. 

2. Permitted by the Austrian law. 

3. Chlopin {p. 185) examined this color, and on his own experiments classifies it as 

"nonpoisonous." The experimental data are as follows: 



132 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Experimental data by Chlopin. 

No, 1. 

[1 gram= 143 mg= 100 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 10 
11 


Grams. 


Kilos. 
7.0 


cc. 
380 
370 
370 
370 


Dog and urine quite normal. 
Do. 


12 






Do. 


13 


3 




Do. 


14 




Urine orange. 
Do. 


15 






390 










Total.. 


4 





No. 2. 
[1 gram=116 mg=81 grains.] 



1901. 
Nov. 3 
4 


3 


8.6 


450 
430 


Dog well; urine normal color; acid; 
Urine orange; no albumen. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 
Color almost normal; no albumen. 

Do. 


no albumen. 


5 


3 






6 




400 
440 
430 
450 
400 




7 


3 
3 






g 






9 






10 


3 






11 






12-14 




















Total.. 


15 





G. T. 527. 

Trade names. — Coerulein S; Alizarin Green; Anthracene Green. 
Scientific name. — Sodium bisulphite compound of coerulein. 
Discovered. — 1879. 
Shade. — Black. Not offered. 

FAVORABLE. 

1. Chlopin {pp. 186-7) examined this color, and on his own experiments reports it as 
* ' nonpoisonous, and not sufficient data to regard it as suspicious." The exper- 
imental data are as follows: 

Experimental data by Chlopin. 

No. 1. 

[1 gram= 147 mg= 103 grains.] 



? Bate. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Mng. 30 
31 


Grams. 
2 


Kilos. 
0.8 


cc. 
320 
330 
300 
330 
300 


Before experiment dog quite normal. 
Urine normal; acid; no albumen. 


Sept. 1 


3 
3 




Do. 




Urine has scarcely perceptible sheen; no albumen. 


3 




Do. 


4 


3 
3 
3 
3 




Do. 


5 




300 


Do. 


g 




Do. 


7 






Nothing abnormal. 
Do. 


9 




310 


10 


2 




Do. 


11 




375 


Do. 


12 18 


. 




Do. 












Total.. 


22 





COMPILED DATA UNDER GREEN TABLE NUMBERS. 
Experimental data by Chlopin — Continued. 

No. 2. 
[1 gram=167 mg=117 grains.] 



133 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Mar. 3 
4 


Grams. 
2 
3 
3 

2 


Kilos. 
6 


cc. 
270 
250 
265 


Before experiment dog quite well; urine normal. 
Urine yellow with orange sheen; acid; no albumen. 


5 




Thin stool twice; urine dark yellow with greenish sheen; acid; 

no albumen. 
Stool normal; urine yellow green; acid; no albumen; general 

condition quite well. 


6 










Total.. 


10 





DOUBTFUL. 

1. WiNOGRADOw {Zts. Nohr. Genussm., 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 530. 

Trade name. — Benzoflavin. 

Scientific name. — Hydrochlorid of diamido-phenyl-dimethyl-acridin. 

Discovered. — 1887. 

Shade. — Brownish orange yellow. Not offered. 



Nothing, 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin (p. 189) on his own experiments regards this color as suspicious. The 
experimental data are as follows: 

Experimental data by Chlopin. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
May 3 


Grams. 
2 


Kilos. 


cc. 
365 
391 


Before experiment dog well and urine normal. 
Dog ate poorly; traces of albumen. 
Do. 




5 


2 





6 




330 
375 


Urine greenish sheen; acid. 
Color same; no albumen. 


7 


2 




8 




Do. 


9 








Do. 












Total.. 


6 





G. T. 532. 

Tradenames. — Phosphin; Xanthin; Leather Yellow ; Philadelphia 
Yellow G. 

Scientific name. — Nitrate of chrysanilin (unsym. diamido-phenyl- 
acridin) and homologues. 

Discovered. — 1862. 

Sliade. — Orange yellow. Not offered. 



FAVORABLE. 



Nothing. 



134 



COAL-TAE COLORS USED TN FOOD PRODUCTS, 



UNFAVORABLE. 

1. Chlopin(p. i90) reports Fuchsin containing Phosphin as suspicious. 

2. On his own experiments s:iys this color ''does not belong to the poisonous colors, 

but is not wholly harmless. ' ' The experimental data are as follows: 

Experimental data hy Chlopin. 
[1 grain=147 mg=103 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Apr. 15 
16 


Grams. 


Kilos. 
6.8 


cc. 
390 
350 
350 


Dog well; urine normal. 
Do. 


2 


17 




Do. 


18 


3 




Urine yellower than normal; vomited several times after taking 
d3^e; no albumen. 


19 




330 
370 


21 


2 




Vomited twice; urine same. 


22 




No vomiting; urine same. 


23 








Color normal. 


24 








Dog well; urine normal. 










Total.. 







3. {p. 178): See experimental data on G. T. 448, which also applies to this color. 

4. Fraenkel (p. 578): Where its physiological action is compared with quinin its 

action on protozoa is far greater. "The Phosphins are locally strong irritants, 
and producers of inflammation of medium poisonous nature so that humans 
can very well bear 400 milligrams, or 6.17 gi'ains. 

5. Lewin {Lehrbuch der Toxihologie, 1897, p. 232): "Phosphin * * * produces 

in humans, in doses up to 1 gram, vomiting and diarrhea.'' 

DOUBTFUL. 

1. WiNOGRADOw {Zts. NaJiT. Genussm., 1903, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 563. 

Trade Tiames. — Alizarin Blue S; Anthracene Blue S; Alizarin 
Blue ABS. 

Scientific name. — Sodium bisulphite compound of dioxyanthra- 
quinone-beta-quinolin. 

Discovered and patented. — 1881 . 

Shade. — Blue. Not offered. 



1. Permitted by law of Austria. 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin (p. 171): On authority not given reports this color as poisonous or harmful. 

2. Ehrlich (Das Sauerstoffbcducrfniss des Organismm, 1885, p. 23): "Per kilogram 

of rabbit, 12-15 cc of this solution in general produce death within the first 
quarter of an hour; whereas 4 cc of the same did not usually produce it, and 
7 cc represent a medium, when properly applied, fatal dose." (This solution 
contained not to exceed 17 per cent coloring matter; each cubic centimeter 
represents 170 milligrams per kilogmm body weight, or llOgi-ainsper 100 pounds; 
the coloring matter was introduced subcutaneously.) 

3. Buss lists it as poisonous. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 135 

G. T. 572. 

Trade name. — Indophenol white; Leucindophenol. 
Scientific name. — Tin compound of dimethyl-para-amido-phenyi- 
para-oxy-alphanaphthylamin. 
Discovered. — 1881 . 
Shade. — ^Blue. Not offered. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Santori {MoleschotVs Untersuchungen, 1895, v. 15, p. 57): A dog weighing 4,000 
grams received 18 grams dye in 30 days, which amounts to 150 milligrams per kilo 
per day or 105 grains per 100 pounds per day. Temperature, urine, and weight 
all remained unchanged. Animal killed with chloroform; autopsy showed 
fatty degeneration of the liver; everything else normal. (Santori classes this 
color as "not nonpoisonous.") 

G. T. 574. 

Trade names. — Ursol D; Ursol P; Ursol DD. 

Scientific name. — Hydrochlorids of para-phenylene diamin, para- 
amidophenol, and diamidodiphenylamin, respectively. 
Discovered. — 1888. 
Shade. — Brown to black. Not offered. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Chlopin (p. 214) examined this color, and on his own experiments reports it as 
"strongly poisonous." On January 15, 1901, a dog weighing 18.4 kilos was 
given 3 grams. An hour or an hour and a half after giving dye vomiting set 
in; dog lay down on one side and died in 3 or 4 hours. Cause of death, 
heart filled with coagulated blood; lungs, liver, and kidneys filled with blood; 
turbid swelling of the liver and heart; mucous membrane of stomach inflamed; 
brain unchanged. Death caused by paralysis of the heart. It also acts 
severely on the skin. 

G. T. 576. 

Trade names. — New Gray; Malta Gray; Nigrosin; Direct Gray; 
Methylene Gray ; New Methylene Gray. 

Scientific name. — ( ?) 

Discovered. — 1888. 

Shade. — Gray. Not offered. ' 

FAVORABLE. 

1. Chlopin {p. 209) examined this color, and on his own experiments concludes it 
contains "no poisonous properties." The experimental data follow: 



136 COAL-TAR COLORS USED IX FOOD PRODUCTS. 

Experimental data by Chlopin. 
[1 gram=77 rag=54 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Feb. 8 
9 


Grams. 
3 


Kilos. 
12.9 


cc. 
510 
480 
400 
450 
475 


Dog quite well; urme quite normal. 
Urine green color; acid; no albumen. 


10 


6 




Do. 


11 


3 
3 
3 
3 
3 




Do. • 


12 




Do. 


13 




Vomited once; urine dark green; acid; no albumen. 


14 


i 


Do. 


15 
16 


12.8 490 


Do. 
Urine lighter shade. 


17 






475 


Urine normal; dog well. 








Total . 


21 





G. T. 584. 

Trade names. — Safranin; Safranin S; Safranin cone; Safranin 
GOO; Safranin T; Safranin extra G; Safranin FF extra; Safranin 
AG, AGT, and OOF. 

Name under which it was offered on the United States marlcet as a 
food color in 1907. — Safranin SP. 

Sdentijic name. — Mixture of diamido-phenyl-and-tolyl-tolazonium 
chlorids. 

Discovered and patented. — 1859. 

Shade. — Reddish brown. Offered bv 1 out of 12 sources. 



FAVORABLE. 



1. Cazeneuve (Arch. gen. de med. 1886, Vol. 
disturbances but is not a violent poison. 



/, p. 753): Produces gastro-intestinal 



unfavorable. 

1. Prohibited by Confectioners' List. 

2. Weyl {p. SI): "Cazeneuve and Lepine pointed out the poisonous nature of 

* * * Safranine." 

3. "This body (Chamber of Commerce of Sonneberg) recommends for the prepara- 

tion of children's toys three colors, the poisonous character of which I can 
demonstrate. These are * * * Safranine * * * . {p. 34.) 

4. Weyl {Ilandhuch der Hygiene): "According to Theodore Weyl this is even in small 

doses, when injected subcutaneously, a strong poison " (50 milligrams per kilo 
body weight, or 85 grains per 100 pounds); "whereas, when administered by 
the stomach only large doses over a long period of time produce diarrhea." 

5. Lewin (Lehrhuch der ToxiJcologie, 1897, p. 232): "Safranin is poisonous when 

injected intravenously. (Pulse acceleration, dyspnoea, cramps.) Fed to doga 
by the mouth it causes only diarrhea." 

6. Prohibited by the Resolutions of the Society of Swiss Analytical Chemists, of 

September, 1891. 

7. Prohibited by the Canton of Tessin. 

8. Buss lists it as poisonous. 

9. Cazeneuve and Lepine (Compt. rend. 1885, v. 101, p. 1011): A dog (weight not 

given) was given, by the mouth, daily doses of from 1 to 4 grams for several 
weeks; only salivation and diarrhea were produced. They conclude that it 
is a harmful color. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 137 

DOUBTFUL. 

1. WiNOGRADOw (Zts. Nahr. Genussm., 1903, v. 6, p. 589) says it almost com- 
pletely inhibits digestion. 

G. T. 593. 

Trade names. — Mauve; Mauvein; Chrome Violet. 
Obsolete names. — Mauve Dye; Anilein; Anilin Purple; Violein; 
Indisin. 

Scientific name. — Salts of phenyl- and tolyl-safranins. 

Discovered and patented. — 1856. 

Shade. — Blue, Reddish Blue, Bluish Violet. Not offered. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

G. T. 599. 

Tradenames. — Indulin, spirit soluble; Indulin opal; Fast Blue R 
and B, spmt soluble; Indulin 3B and 6B, spirit soluble; Indulin 3B 
opal; Indulin 6B opal; Azin Blue, spirit soluble; Indigen D and F; 
Printing Blue ; Ace tin Blue. 

Scientific name. — Mixtures of dianilidoamido, trianilido and tetra- 
anilido phenyl-phenazonium chlorids. 

Discovered and patented. — 1863. 

Shade. — Blue. Not offered. 

FAVORABLE. 

1. Santori {MoleschotVs Untersuchungen, 1S95, v. 15, p. 50): A dog weighing 4,600 
grams received 12.5 grams of this dye (in oil) in 30 days, which amounts to 91 
milligrams per kilo per day, or 64 grains per 100 pounds per day. There was no 
disturbance of any kind. Killed by chloroform; autopsy showed everything 
to be normal. 

G. T. 600. 

Trade names. — Nigrosin, spirit soluble; Coupler's Blue; Oil Black; 
Sloelin ; Spirit Black. 

Scientific name. — Mixtures of Indulins with allied bases and fluorin- 
dins. 

Discovered and patented. — 1867. 

Shade.— Blsick. Not offered. 

FAVORABLE. 

1. Permitted by Confectioners' List. 

G. T. 601. 

Trade names. — Indulin, soluble; Indulin 3B; Fast Blue R and 3R; 
Sloelin R S and B S ; Induhn R and B ; Indulin 6 B ; Fast Blue 2R, B, 
and 6B. 



138 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



Scientific name. — Mixtures of the sodium salts of the sulphonic 
acids of the various spirit-soluble induhns. 
Discovered and patented. — 1867. 
Shade. — Bronzy or Blue Black. Offered by 1 out of 12 sources. 

FAVORABLE. 

1. Chlopin {pp. 198-9): On his own experiments classifies this color as nonpoisonous. 
The experimental data are as follows: 

Experimental data by Chlopin. 

No. 1. 
[1 grain=54 ing=38 grains.] 



Date. 


Dose. 


Ay eight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Jan. 5 
6 


Grams. 
3 


Kilos. 

18.4 


cc. 
650 
670 
400 
410 
400 
400 
500 
560 
650 
620 


Dog and urine normal. 

Urine brown; acid; no albumen. 


7 


3 
3 
3 
3 
3 




Urine greenish brown; no albumen. 


8 




Do. 


9 




Do. 


10 




Do. 


11 




Do. 


12 




Do. 


13 






Do. 


14 






Color and composition of urine normal; dog is well. 


Total . 


18 







No. 2. 
[1 gram=114 mg=80 grains.] 



1902. 
Jan. 14 
15 


3 
3 
3 


8.8 


420 
390 


Dog and urine normal. 

Urine slightly blue; acid; no albumen. 

Do. 

Do. 
Urine almost nonnal color; no albumen. 
Color and other properties of urine normal- 
No record. 
Urine slightly bluish; no albvunen. 

Do. 
Dark green; no albumen. 
Feeble green; no albumen. 
Urine nonnal; dog well. 




16 






18 




420 




19 








20 









21 


3 
3 
3 


8.8 






22 


400 
460 
400 
450 
400 




23 






24 






25 








26 
















Total. 


18 





UNFAVORABLE, 

1. Santori (Moleschott^s Untersuchungen, 1895, v. 15, p. 55): A dog weighing 4,500 
grams received 4 to 6 grams dye in 7 days, which amounts to 127 to 190 milli- 
grams per kilo per day, or 89 to 133 grains per 100 pounds per day. No vomiting. 
Stool black blue and no change in the urine. Up to the sixth day the animal, 
in very good general condition, ate heartily and was quite lively; temperature 
imchanged. On the morning of the sixth day the animal was found in his cage 
suffering fi'om general muscular cramps which were heightened by the slightest 
noise; the animal did not respond to calls or threatening movements and was in 
a complete stupor. This continued for 24 hours, when the animal died. The 
autopsy showed numerous punctures of the lungs and of the mucous membrane 
of the stomach; fatty degeneration of the liver and little blood in it; kidneys 
without change, although the cortex was colored a light green. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



139 



G. T. 602. 

Trade names. — Nigrosin, soluble; Bengal Blue; Gray R and B. 
Scientific name. — Sodium salts of sulphonic acids of spirit nigro- 
sins. 

Discovered and 'patented. — 1867. 
Shade. — Black. Not offered. 



Nothing. 



FAVORABLE . 



UNFAVORABLE . 



1. Lewin {Lehrhuch der Toxikologie, 1897, p. 231) says: ''Produces eczema," and 
cites Deutsche. Med. Wochenschr., 1891, page 4-5. 

G. T. 614. 

Trade names. — Magdala Red; Naphthalene Rose; Sudan Red; 
Naphthalene Red; Naphthylamin Pink. 

Scientific name. — Mixture of amido-naphthyl-naphthazonium- 
chlorid and diamido-naphthyl-naphthazonium chlorid. 

Discovered. — 1868. 

Shade. — Red. Not offered. 



Nothing. 



FAVORABLE. 
UNFAVORABLE . 



1. Chlopin (p. 200) examined this color, and on his own experiments concludes it 
"does not belong to the poisonous list, but is not wholly harmless." The ex- 
perimental data are as follows: 

Experimental data by Chlopin. 

No. 1. 
[1 gram=91 ing=64 grains.] 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Apr. 12 
13 


Grams. 
2 


Kilos. 
11 


cc. 
ISO 

1,100 
760 
660 
670 


Before experiment dog and urine normal. 


14 


3 




Do. 


15 




Urine quite red; acid; no albumen; vomited once. 
Xo vomiting; dog is well; iirine normal in color and compo- 
sition. 


18 














Total . 


' 







Mo. 2. 
[1 gram=lll mg=78 grains.] 



1903. 
eb. .^ 

4 


3 
3 
3 


9 


380 
340 
370 


5 




6 




7 


3 
3 






8 




310 
320 


9 










Total . 


u 



Day Ijefore experiment quite well; urine normal color; acid; no 

albumen. 
In the morning three times thin stool, urine faintly rose-colored; 

acid; no albumen. 
No diarrhea; urine rose-red; acid; no albumen. 
Do. 
Do. 
Do. 
Do. 



140 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Experimental data by Chlopin — Continued. 
[1 grain=114 mg=80 grains.] 



Date. 


Dose. 


AVeight. 


24 hours' 
urine. 


General condition of animal and urine. 


1903. 
Feb. 10 


Grams. 
3 


Kilos. 


CO. 

310 

315 
350 


Vomiting and diarrhea; urine rose-red; no albumen; acid; with 
muriatic acid rose color, becomes greenish gray. 


11 




12 




8.8 


No vomitin?; no diarrhea; color reaction of urine normal; no 






albumen. 


Total . 


3 





DOUBTFUL. 

1. WiNOGRADOvv {Zts. NaliT . Gcnussm. 190S, v. 6, p. 589) says it almost completely 
inhibits digestion. 

G. T. 620. 

Trade names. — Gallocyanin DH and BS; Fast violet; Gallocyanin 
RS, BS, and D. 

Scientific name. — Dimethylamido dioxy phenazoxoniumcarboxy- 
late. (BS is the bisulpliite compound.) 

Discovered and patented. — 1881. 

Shade. — Bluish Violet. Not offered. 



Nothing:. 



FAVORABLE. 



UXFAA'ORABLE. 



1. Santori {MoleschotV s Untersuchungcn, 1895, v. 15, p. 51): A dog weighing 5,400 
grams received 7.5 grams dye in 30 da}'s^ which amounts to 46 milligrams per 
kilo per day or 32 grains per 100 pounds per day. Throughout all the time 
the animal remained well, had good appetite, temperature normal, no loss of 
weight; urine and feces colored deep blue black. Killed by chloroform. 
Autopsy showed incipient fatty degeneration of the liver and a swelling of the 
kidneys. Conclusion: Poisonous. 

G. T. 639. 

Trade names. — Meklola^s Blue; Cotton Blue R; Fast Navy Blue 
R; Naphthol Blue R and D; Naphthylene Blue R in crystals; Fast 
Blue R, 2 R and 3 R for cotton in crystals; Fast Nav^^ Blue RM 
and ^£M. 

Scientific name. — Zinc double clilorid of dimethylamido-naphtho- 
phenoxazonium clilorid. 

Discovered. — 1879. 

Shade. — Dark Violet. Not ofl'ered. 

favorabi>k. 
Nothing. 

UNFAVORABLE. 

1. Chlopin {j)p. 194-195) on his own experiments reports this color as "very poison- 
ous." The experimental data are as follows: 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 

Experimental data by Chlopin. 
No. 1. 
[1 gram=68 mg=48 grains.] 



141 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Jan. 5. . . 


Grams. 
3 


Kilos. 
14.6 


cc. 

590 


Before experiment dog quite well; urine normal in color and 
composition; 1 hour after giving the dye vomiting began; 
dog lay down on ground and died in 1 hour. 


Total . 


3 





No. 2. 
[1 gram=167 mg=117 grains.] 



1902. 
Jan. 14 


3 
3 


6 




15 










Total . 


6 



Soon after giving dye, strong vomiting and diarrhea; after a feir 

hours improved. 
Most violent vomiting; dog lay down on his side, and was foxinfi 

dead in 6 hovirs. 



Note.— See p. 181. 

2. Santori (Moleschotfs Untersuchungen, 1895, v. 15, p. 49): A dog weighing 4,50S 
grams received 12.5 grams dye during 30 days; this amounts to 93.3 milligrams 
per kilo per day or 65.3 grains per hundred pounds per day. Continued vom- 
iting beginning with 0.2 grams dye, anaemia and copious as well as continuoxi® 
salivation and emaciation; the animal lost 1,200 grams in weight or 27 per 
cent. Killed by chloroform; autopsy showed no fat, flabby muscles, Btomack 
contracted and filled with mucous and in part colored pea green; fatty degen- 
eration of the liver; contracted bladder; kidneys swollen and congested with 
blood and decomposed blood corpuscles in the Bowman capsules. 

G. T. 649. 

Trade names. — Gentianin; Gentiana Molet. 

Scientific name. — Zinc double chlorids of dimethyldiamido phe- 
nazthionium chlorid. 

Discovered and patented. — 1886. 
SJiade. — Violet. Not offered. 



Nothing. 



FAVORABLB. 



UNFAVORABLE. 



Santori {MoleschoiVs Untersuchungen, 1895, t\ 15, p. 54): A dog weighing 3,00€* 
grams received 4.7 grams of dye in 7 days, which amounts to 224 milligrams per 
kilo per day or 157 grains per 100 pounds per day. Beginning with the thii^ 
day the dog appeared weak and depressed and a whitish froth appeared at. 
the mouth; mild diarrhea and complete aversion to food; temperature and 
urine unchanged. Died on seventh day. Autopsy showed congestion of 
mucous membrane of stomach; the liver was inflamed and the kidneys strong! j 
congested. 



142 COAL-TAB COLORS USED IN FOOD PRODUCTS. 

G. T. 650. 

Trade Thames. — Methylene Blue B and BG; Methylene Blue BB in 
powder extra D; Methylene Blue BB in powder extra; Methylene 
Blue A extra. 

Names under which it was offered on the United States marJcet as a 
food color in 1907. — -Methylene Blue B; Methylene Blue. 

Scientific name. — Chlorid or zinc double-chlorid of tetramethyl- 
diamido-phenazthionium. 

Discovered. — 1876. 

Shade. — Blue. Offered by 2 out of 12 sources. 

FAVORABLE. 

1. ScHACHERL (p. 1046): "To these groups belong the much-used Methylene Blue, 

which in moderate doses is harmless." 

2. Fraenkel {p. 574): "* * * Methylene Blue causes no noteworthy disturb- 

ances." 

3. Cazeneuve {Arch. gen. de. med. 1886, v. 1, p. 753) says that it produces gastric 

intestinal derangements but is not a violent poison. 

unfavorable. 

1. Prohibited by Confectioners' List. 

2. Weyl (p. SI): "Cazeneuve and Lepine pointed out the poisonous natiu*e of 

* * * Methylene Blue * * *." 

3. Fraenkel (p. 579): "To regard Methylene Blue as a specific remedy such as 

quinin, is, in spite of a few such experiments, improper; it produces sub- 
sidiary effects which depend in part upon local irritation of the intestinal tract, 
and partly, however, upon irritation of the bladder with increased micturi- 
tion." 

4. Cazeneuve {Arch. gen. de med. 1886, v. 1, p. 753), says that it produces gastric 

intestinal derangements. 

5. Combemale and Francois {Sem. Med. 1890, no. 31, p. 258), say that it produces 

intestinal disorders and vomiting, colored urine, and colored feces in dogs, 
and therefore is a highly injurious color. 

6. Santori (il/oZesc^o«'s Untersuchungen, 1895, v. 15, p. 42) classes it as injurious. A 

dog weighing 4,600 grams received in 20 days 18 grams dye, which amoimts to 
196 milligrams per kilo per day, or 137 grains per 100 pounds per day. Urine 
and feces colored; diarrhea and continuous vomiting; blood and pus contained 
in stool; loss of appetite; loss of weight was 1,600 grams, or 35 per cent. Animal 
died. Autopsy disclosed blue-colored skin and fat; brain turned blue on 
exposure to air, but only the outer cortex was colored; stomachical catarrh; 
the mucous membrane of the stomach colored blue; the heart sac and the 
pleura colored blue to blue-green; intestines externally blue; kidneys were 
thickened and colored dark blue throughout; parenchymatous kidney inflam- 
mation; fatty degeneration of the liver; diaphragm locally colored. 

7. Arloing and Cazeneuve, quoting Cazeneuve and Lepine {Arch, de med. v. 9, 

p. 364), say that it is not inactive. 

8. Forbidden by Resolutions of Swiss Analytical Chemists, September, 1891. 



COMPILED DATA UNDER GEEEN TABLE NUMBERS. 143 

9. Galliard (Rev. intern, des falsifications; abst. Hygien. Runsdach. 1892, p. 104)'- 
"Methylene Blue, which is frequently used for coloring foods, can cause, even 
in small doses (10 to 20 milligrams, or one-sixth to one-third of a grain), a feel- 
ing of general depression, nausea, and certain feelings of pain, and can even 
produce transitory albuminuria. In larger doses (40 to 60 milligTams, or six- 
tenths to nine- tenths of a grain), it causes in the case of persons not accustomed 
thereto, vomiting, diarrhea, increased micturition, and albuminuria. In the 
case of persons suffering from nervous diseases, it frequently produces disturb- 
ance which has as its consequence a cessation or a change of place of the pain. 
Sometimes it produces painlessness, or an easing of pain in the patient, for 
which no certain therapeutic indication could be determined." 

10. Weyl {Handhuch der Hygiene) comments as follows: ''These statements of Gal- 

liard arouse but little confidence, because, as is well known, Methylene Blue 
is very frequently administered to invalids in doses of more than 0.5 gram 
without any noticeable disturbance. Perhaps Galliard's preparation was 
unclean. At any rate, in all experiments on the poisonous nature of Methylene 
Blue it is to be considered that it frequently occurs in commerce as a zinc 
chlorid double salt." 

11. Lewin (Lehrbuch der ToxiJcologie, 1897, p. 232): "Methylene Blue * * * caD 

produce after prolonged administration of 0.5-1.5 gram daily increased micturi- 
tion, irritation of the bladder, blue coloration of the urine, and saliva, diarrhea^ 
headaches, vertigo, delirium, and twitching of the muscles, the latter symp- 
toms probably because the coloring matter is deposited in the brain." 

12. Buss lists it as poisonous. 

G. T. 651. 

Trade name, — Methylene Green G cone, extra ^^ellow shade. 
Scientific name. — Nitromethylene Blue. 
Discovered and patented. — 1886. 
STiode. — Green. Not offered. 

FAVORABLE. 

Nothing. 

UNFAVORABLE. 

1. Chlopin (pp. 192-193) examined this color, and on his own experiments concludes 
that it is "nonpoisonous, but somewhat suspicious." The experimental data 
are as follows: 

Experimental data by Chlopin. 

No. 1. 

[1 gram=71 mg=50 grains.] 



Date, i Dose, i ^"^'^il?^*- j urj^^' j General condition of animal and urine. 



1901. I Grams. \ Kilos, i cc. 

Apr. 24 2 i 14 580 Dog well; urine normal. 

25 I Urine dark green; acid: no albumen. 

26 j i i iTine less colored; acid; traces of albumen. 

28 I 2 ' No record. 

29 ! ; Urine dark brown; no albumen; acid. 

30 _ ; 485 I Do. 

May 2 ' \ ; Color normal; acid; no albumen. 

Total.': 4 I ! 



144 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Experimental data by Chlopin — Continued. 

No. 2. 
[1 gram=122 mg=85 grains.] 



Bate. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 

• 


1901. 
Hov. 25 

26 


Grams. 
3 
3 
3 
3 
3 


Kilos. 
8.2 


cc. 
430 
445 
450 
410 
440 


Dog well; urine normal. 
Urine strongly green; no albumen. 
Do. 


27 




28 

29 

Bee. 1-2 




Diarrhea; urine green; acid; no albumen. 

No diarrhea; urine same. 

Color normal; acid; no albumen; dog lively and well. 










Total . 


15 





DOUBTFUL. 

1. WiNOGRADOW (Zts. Nalir. Genussvi., 190S, r. 6, p, 589), says it noticeably retards 
digestive action; is not indifferent. 

G. T. 654. 

Trade name. — Toluidin Blue O. 

Scientific name. — Zinc-double-chlorid of dimethyl-diamido-tolu- 
phenazthonium-chlorid. 

Discovered and patented. — 1888. 
Shade. — Blue. Not offered. 



Nothino;. 



FAVORABLE. 



UNFAVORABLE. 



I. Fraenkel (p. 57.^): "Toluidin Blue * * * is a strong poison for micro- 
organisms, and may be used in eye treatment, like Methylene Blue." 

G. T, 659. 

Trade names. — Primulin; Tliiochromogen ; Sulphin; Polychromin; 
Aureolin. 

Scientific name. — Sodium salt of the mono-sulphonic acids of the 
dehydrothionated condensation products of dehydrothiotoluidin 
(mixed with some sodium dehydrothiotoluidin-sulphonate). 

Discovered. — 1887. 

SJiade. — Yellow. Not offered. 



Nothing. 



FAVORABLE. 



UNFAVORABLE. 



1. Chlopin (p. 203) examined this color, and on his own experiments reports it aa 
*8Uspicious." The experimental data are as follows: 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 

Experimental data hij Chlopin. 
[1 gram=154 mg=108 grains.] 



145 



Date. 


Dose. 


Weight. 


^tirine'^'^ General condition of animal and urine. 


1902. 
Mar. 21 
22 


Grams. 
2.0 


laios. 
6.5 


cc. 

292 
294 


Dog and urine normal. 


23 


3.0 
10.5 




355 
2G0 




24 
25 


6.3 


Urine darlv brown; acid; no albmnen. 
Do. 


26 






No albumen: dark-brown color; dog h;xs lassitude; does not eat 

bread nor take milk, only a little meat. 
No albiunen; dark-brown color; dog has lassitude; dog eats 

little. 
At the point of injection an abscess appears; urine acid; no 

albumen; yellow color. 
Urine acid; no albumen; yellow color; dog eats more. 
Urine acid; no albumen; Vellow color; abscetss broke. 


27 






291 


.8 






29 






270 
295 
280 


30 






Apr. 2 






Urine normal: appetite almost normal. 






Total . 


/ 15.0 
\ 2 0.5 







By mouth. 



2 Subcutaneouslv. 



2. See also Chlopin" (Zts. N'ahr. Genussm., 1902, v. 5, p. 241). 



DOUBTFUL 



1. Wi>:oGRADOW'<Z/.s. Xahr. Genussin., 190S, v. 6, p. 589) says it noticeably retards 
digestive action: is not indifferent. 

G. T. 667. 

Trade names. — Quinoliii Yellow; Quinolin Yellow, water-soluble. 

Name under loMch it was offered on the United States marlcet as a 
food color in 1907. — Cliinolin Yellow O. 

Scientific name. — Sodium salt of the sulphonic acid (chiefly 
disulphonic acid) of quinophthalone. 

Discovered. — 1 882 . 

Shade. — Greenish Yellow. Offered by 1 out of 12 sources. 



Nothino:. 



FAVORABLE, 



UNFAVORABLE. 



1. Chlopin (p. 205) on his own experiments reports this color as "suspicions, 
experimental data are as follows: 

Experimental data hij Chlopin. 

No. 1. 
[1 graui=44 mg=31 grains.] 



The 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1902. 
Mar. 19 
20 


Grams. 
3.00 


Kilos. 
22.6 


cc. 
730 
720 

749 


Before experiment dog and urine normal. 
Urine dark brown; traces albumen; acid. 


21 






22 






Do. 



97291°— Bull. 147—12- 



-10 



146 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Experimental data by Chlopin — Continued. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


l'.)02. 
Mar. 23 
24 


Grams. 
0.75 


Kilos. 
21.4 


cc. 
750 


Urine dark brown; no albumen. 
Dog eats nothing. 


25 






693 
725 


Do. 


26 






Do. 


27 






Dog eats nothing; eats poorly; albumen in urine. 
Dog eats nothing; rather much albumen. 


28 








29 








Do. 


30 








Do. 


Apr. 2 

4 








Dog eats nothing: traces of albumen. 


13.66 




710 


Color of urine almost normal; insignificant traces of albumen. 






Urine yellow brown; traces of albumen; appetite normal. 


6 








Urine yellow brown; no albumen. 


8 






700 


Urine and dog nonnal. 










Total.. 


f 16.00 
\ 2 0. 75 





No. 2. 

[1 gram= 133 mg=83 grains.] 



1903. 

Mar. 3 3.00 

4 i 3.00 

5 I 3.00 

6 ; 2.00 



7.5 



Total.. 11.00 



320 
300 
300 



Before experiment dog quite well, and urine normal. 
Color dark yellow; no albumen; general condition normal. 
Color yellower than normal; acid; no albumen. 
Do. 



By mouth. 



2 Subcutaneously. 



DOUBTFUL. 



1. WiNOGRADOw {Zts. Nahr. Genussm., 1903, v. 6, p. 589) says it noticeably retards 
digestive action; is not indifferent. 

G. T. 670. 

Trade names. — Vidal Black; Vidal Black S. 

Scientific name. — Possibly the sulpho-hydro derivative of a 
polythiazin. 

Discovered. — 1893. 

Shade. — Green. Not offered. 



Nothing:. 



FAVOR.\BLE. 
UNFAVORABLE. 



1. Chlopin {p. 208) examined this color, and on his own experiments classeo it as 
" very harmfid. " The experimental data are as follows: 

Experimental data by Chlopin. 
[1 gram = l.T2 mg=92 grains.] 



Daie. 


Dose. 


Weight. 


24 hours' 
urine. 


General condition of animal and urine. 


1901. 
Dec. -29 

•iO 


(Jrams. 
3 


Kilos. 
7.6 


cc. 

380 

390 


Before experiment dog quite normal; soon after taking dye 

vomited twice. 
(Jonoral condition good; no vomiting; urine turbid, alkaline; no 






albumen. 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 
Experimental data by Chlopin — Continued. 



147 



Date. 


Dose. 


Weight. 


urin^e ^ 1 General condition of animal and nrlne. 


1901. 
Dec. 31 


Grams. 
3 

3 


Kilos. 


cc. 


Vomited soon after getting dye; appetite less; no albumen. 
Urine turbid: scarcely noticeable blackish sheen; green with sul- 


1902. 
Jan. 1 






2 


7 


3(;9 

370 


phuric and hydrochloric acid. 
Do. 


4 


3 
3 


Vomited all day after taking dye; eats little; no albumen. 


5 




Violent and prolonged yomiting and diarrhea; condition piti- 


6-7 






able; further giving of dye stopped , so as not to kill the animal. 
Vomiting and diarrhea continue. 
Vomiting and diarrhea h^topped. 


8 








9-11 








Dog is liyelier, and begin - to eat. 

Dog looks well; urine normal in color; acid; no albumen. 


13 
















Total.. 


17 





G. T. 675. 

Trade names. — Thiocatechin; Thiocatechin S. 
Shade. — Brown. Not offered. 



Nothini:. 



FAVOR.\BLE. 



UXFAVORABLE 



1. Chlopix (pp. JIO. -ilT) examined this color and classes it as "very poisonous." 
The experimental data are as follows: 

Experimental data by Chlopin. 
[1 gram=128 mg=90 grains.] 



General condition of animal and urine. 



Date. 


Dose. 


Weight. 


24 hours' 
urine. 


1902. 
Feb. 13 

14 


Grams. 
2.4 

2.0 
0.5 


Kilos. 

7.8 


cc. 

300 

290 


15 




l(i 






18 
















Total.. 


4.9 



Before experiment dog and urine quite normal; 10 or 15 minutes 
after giving dye dog fell on one side, limbs extended, stomach 
drawn in; small and frequent convulsions; retching; thea 
abundant vomiting, same color as dye; soon after vomiting dog 
got up and walked as if drunk; hind legs tend to collapse; sali- 
vation. 

A few minutes after giving dye, dog again fell as if in an epileptic 
fit; convulsions of the extremities, whicli soon ceased, but the 
dog still lay stretched out, with open eyes, which reacted to 
light; tongiae hanging out to one side; after 10 or 15 minutes 
vomiting began; dog still lying on one side, assumed a more 
normal attitude; 15 minutes later dog got up, walked as if 
drunk; poor control over hind legs. 

Vomits at once after getting dye, but remained standing. 

Dog appears depressed, but eats. 

Dog quite well; urine usual normal color; no albumen. 



G. T. 689. 



Trade names. — Indigo ; Indigo Pure BASF. 
Scientific name. — Indigo tin. 
Sluule. — Blue. Not offered. 



148 



COAL-TAR COLOES USED IN FOOD PRODUCTS. 



FAVORABLE. 

1. Permitted by Confectioners' List. 

2. Permitted by the law of Italy. 

UNFAVORABLE. 

1. Fraenkel (p. 571): "However, pure Indigo, according to Robert, is, in finely 
divided condition, a violent local irritant." 

G. T. 692. 

Trade names. — Indigo Carmine; Indigo Extract; Indigotin. 

Names under wliicJi it was offered on the United States marlcet as a 
food color in 1907. — Indigo Carmine Powder IN; Indigotin; Indi- 
gotin A. 

Scientific name. — Sodium salt of Indigotin disulphonic acid or the 
free acid. 

Discovered. — 1740. 

Shade. — Blue. Offered by 3 out of 12 sources. 

favorable. 

1. Schacherl (p. 1046): " No objection to its nse." 

2. Santori { MolcschoW s Untcrsuchungen, 1895, v. 15, p. 41)' A dog weighing 4,500 

grams received 90 grams dye in 30 days; vomited twice during the examina- 
tion; no change in weight; animal killed with chloroform; autopsy showed 
slight dull swelling in the epithelium and convoluted canals of the kidneys. 
This dosage amounts to 667 milligrams per kilo per day, or 467 grains per 100 
pounds per day. Classes it as harmless. 

ALPHABETICAL INDEX OF TRADE NAMES OF COAL-TAR COLORS. 

The following list of the trade names of coal-tar colors appearing 
in the foregoing compilation on physiological action is complete 
when supplemented by the list of 23 colors given on page 227; 
Green Table numbers in parenthesis. 



Acetin Blue (599). 
Acid IBrown (138). 
Acid Green (434,435). 
Acid Green ex. cone. (435). 
Acid Green cone. (435). 
Acid Green cone. VN (435). 
Acid Green cone. 780 (435). 
Acid Fuchsin (462). 
Acid Magenta (462). 
Acid Magenta powd. (462). 
Acid Rosein (462). 
Acid Rubin (462). 
Acid Violet (467). 
Acid Violet 6 B (467). 
Acid Yellow (8). 
Acid Yellow AT (94). 
Acid Yellow D (88). 



Acid Yellow G (8). 
Acid Yellow G pat. (8). 
Acme Yellow (84). 
Alizarin Blue ABS (563). 
Alizarin Blue S (563). 
Alizarin Green (527). 
Alphanaphthol Orange (85). 
Alsace Green (394). 
Amaranth (107). 
Amaranth B (107). 
Anilein (593). 
Anilin Blue Sp. Sol. (457). 
Anilin Orange (2). 
Anilin Purple (593). 
Anilin Red (448). 
Anilin Yellow (4). 
Anilin Yellow S (4). 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



149 



Anthracene Green (527). 

Anthracene Blue S (563). 

Archil Substitute V (28). 

Atlas Orange (86). 

Auramin (425). 

Auramin O (425). 

Aurantia (6). 

Aureolin (659). 

Aurin (483). 

Azalein (408). 

Azarin S (70). 

Azin Blue, spirit soluble (599). 

Azo Acid Rubin (103). 

Azo Acid Yellow (92). 

Azo Blue (287). 

Azo Flavin (92). 

Azo Fuchsin G (93). 

Azo Rubin (103). 

Azo Rubin A (103). 

Azo Rubin S (103). 

Bavarian Blue DBF (479). 

Bavarian Blue DSF (478). 

Bengal Blue (602). 

Bengal Green (427). 

Benzoflavin (530). 

Benzopurpurin 4B (277). 

Betanaphthol Orange (86). 

Biebrich Scarlet (163). 

Bismarck Brown (197). 

Bismarck Brown R (201). 

Bitter-almond-oil Green (427). 

Bleu de Nuit (457). 

Bleu Lumi^re (457). 

Bleu Marine (480). 

Bordeaux B (65). 

Bordeaux B L (65). 

Bordeaux R ext. (65). 

Bordeaux S (107). 

Brilliant Black B (188). 

Brillant Cotton Blue, greenish (479). 

Brilliant Green (428). 

Brilliant Orange (13). 

Brilliant Scarlet (106). 

Brilliant Scarlet 4R (106). 

Brilliant Yellow (5). 

Brilliant Yellow S (89). 

Butter Yellow (16). 

Canary Yellow (425). 

Carbazotic Acid (1). 

Cardinal 3B (103). 

Carminaph (11). 

Carmoisin (103). 

Carmoisin B (103). 



Cerasin (102). 
Cerasm Orange I (11). 
China Blue (480). 
Chlorin (394). 
Chrome Violet (593). 
Chrysamin R (269). 
Chrysaurein (86). 
Chryseolin (84). 

Chrysoidin Crystals (17, 18, 41). 
Chrysoidin R (17, 18, 41). 
Chrysoidin Y (17, 18, 41). 
Chrysoin (84). 
Chrysoin REZ (84). 
Cinnamon Brown (197). 
Citronin (4). 
Claret Red (65). 
Claret Red RZ (103, 106, 107). 
Coerulein S (527). 
Cochineal Red A (106). 
Congo Red (240). 
Cotton Blue (480). 
Cotton Blue R (639). 
Cotton Red 4B (277). 
Coupler's Blue (600). 
Crocein Orange (13). 
Crocein Orange 10234 (13). 
Crocein Orange G (13). 
Crocein Scarlet (106). 
Crocein Scarlet 3B (160). 
Crocein Scarlet 4BX (106). 
Crocein Scarlet 7B (169).- 
Crocein Scarlet 8B (169). 
Curcumin (89). 
Curcumin S (399). 
Dahlia (450, 451). 
Dark Green (394). 
Diamond Green B (427). 
DianthinG(516). 
Dinitro-cresol (2). 
Dinitrosoresorcin (394). 
Diphenylamin Blue (479). 
Diphenylamin orange (88). 
Direct Gray (576). 
Direct Violet (451). 
Emerald Green (428). 
Emerald Green cryst. (428). 
English Brown (197). 
Eosin (512). 
Eosin A (512). 
Eosin A ex. (512). 
Eosin B (512). 
Eosin bluish (517). 
Eosin G G F (512). 



150 



COAL-TAR COLOES USED IN FOOD PRODUCTS. 



Eosin J (512, 517). 

Eosin 10 B (521). 

Eosin 3 J & 4 J ext. (512). 

Eosin Y (512). 

Eosin Yellowish (512). 

Erika B (78). 

Erythrobenzin (448). 

Erythrosin (517). 

Eiythrosin B (517). 

Erythrosin D (517). 

Erythrosin G (516). 

Erythrosin yellow shade (517). 

Ethyl Green (428). 

Fast Blue (477). 

Fast Blue B, spirit soluble (599). 

Fast Blue R and 3R (601). 

Fast Blue R, spirit soluble (599). 

Fast Blue 2R, B, and 6B (601). 

Fast Blue R, 2R, and 3R (639). 

Fast Brown G (138). 

Fast Green (427). 

FastGreen J (428). 

Fast Green O (394). 

Fast Myi-tle Green (394). 

Fast Navy Blue R (639). 

Fast Navy Blue RM and MM (639). 

Fast Ponceau B (163). 

Fast Red (102, 105). 

Fast Red C (103). 

Fast Red D (107). 

Fast Red EB (107). 

Fast Violet (620). 

Fa8tYellow(4, 8, 9, 88). 

Fast Yellow extra (8). 

Fast Yellow G (8). 

Fast Yellow 053 (8). 

Fast Yellow R (9). 

Fine Blue (457). 

Fuchsiacin (448). 

Fuchsin (448). 

Fuchsin cryst. (448). 

Fuchsin S (462). 

Gallocyanin DH and BS (620). 

Gallocyanin RS, BS, and D (620). 

Gentian Blue 6B (457). 

Gentiana Violet (649). 

Gentianin (649). 

Gold Orange (86). 

Gold Yellow (84). 

Golden Yellow (2, 3). 

Gray Rand B (602). 

Green E (428). 

Green 087 (428). 

Guinea Green (433). 



Harmalin (448). 

Helianthin (87). 

Helvetia Blue (479). 

Hessian Blue (457). 

Hofmann Violet (450). 

Hydrazin Yellow (94). 

Imperial Scarlet (163). 

Imperial Yellow (6). 

IndigenDandF(599). 

Indigo (689). 

Indigo Carmine (692). 

Indigo Carmine powd. IN (692). 

Indigo extract (692). 

Indigo pure BASF (689). 

Indigotin (692). 

Indigotin A (692). 

Indisin (593). 

Indisin R and B (601). 

Indophenol (572). 

Indophenol white (572). 

Indulinopal. (599). 

Indulinsol. (601). 

Indulin, spirit soluble (599). 

Indulin 3B opal. (599). 

Indulin 6B opal. (599). 

Indulin 3B sp. sol. (599). 

Indulin 6B sp. sol. (599). 

Indulin 3B (601). 

Indulin 6B (601). 

lodeosin B (517). 

lodeosin G (516). 

lodin Green (459). 

lodin Violet (450). 

Jaune Acide (4, 8). 

Jaune Acide C (4). 

Jaune Naphthol (3). 

Jaune d'Or (3). 

Jaune d' Orient (516). 

Jaune Soleil (399). 

Kaiser Yellow (6). 

Kermesin Orange (97). 

Leather Brown (197). 

Leather Yellow (532). 

Lemon Yellow (4). 

Light Green S F bluish (434). 

Light Green S F yellow shade (435). 

London Blue extra (480) 

Magdala Red (614). 

Magenta (448). 

Magenta F A B S Red (448). 

Magenta Powder A (448). 

Maize (399). 

Malachite Green (427). 

Malachite Green B (427-428). 



COMPILED DATA UNDER GREEN TABLE NUMBERS. 



151 



Malta Gray (576). 

Manchester Brown (197). 

Manchester Brown EE (201). 

Manchester Yellow (3). 

Mandarin G R (97). 

Mandarin G ext. (86). 

Martins Yellow (3). 

Mauve (593). 

Mauve Dye (593). 

Mauvein (593). 

Meldola's Blue (639). 

Metanil Yellow (95). 

Methyl Blue water soluble (478). 

Methyl Blue for silk MLB (478). 

Methyl Blue O (479). 

Methyl Violet (451). 

Methyl Violet B (451). 

Methyl Violet BB ext. (451). 

Methyl Violet 3 BD (451). 

Methylene Blue (650). 

Methylene Blue A ext. (650). 

Methylene Blue B and BG (650). 

Methylene Blue B D (650). 

Methylene Blue BB extra (650). 

Methylene Blue BB extra D (650). 

Methylene Gray (576). 

Methylene Green G. cone. ext. (651). 

Naphthalene Pink (614). 

Naphthalene Red (614). 

Naphthalene Rose (614). 

Naphthol Black B (188). 

Naphthol Black BDF (188). 

Naphthol Blue R&D (639). 

Naphthol Green (398). 

Naphthol Green B (398). 

Naphthol Orange (85). 

Naphthol Red S (107). 

Naphthol Yellow (3, 4). 

Naphthol Yellow L (4). 

Naphthol Yellow S (4, 5), 

Naphthol Yellow SLOZ (4, 86). 

Naphthylamin Yellow (3). 

Naphthylene Yellow (2). 

Navy Blue B (478). 

NewCoccin (106). 

New Gray (576). 

New Green (427). 

New Methylene Gray (576). 

New Red L (163). 

New Victoria Green (427, 428). 

New Yellow (88). 

New Yellow L (8). 

Nicholson Blue (477). 

Night Green (459). 



Nigrosin (576). 

Nigrosin sol. (602). 

Nigrosin sp. sol. (600). 

Nitrodiphenylamin (6). 

Nitromethylene Blue (651). 

Oil Black (600). 

Oil Orange 7078 (11). 

Oil Yellow (16). 

Opal Blue (457). 

Orange (86). 

Orange I (85). 

Orange II (86). 

Orange III (87). 

Orange IV (88). 

Orange A (86). 

Orange A extra (86). 

Orange Brown (17, 18, 41). 

Orange A 1201 (86). 

Orange B (85). 

Orange extra (86). 

Orange G (14). 

Orange GG (14). 

Orange GG Crystals, (14). 

Orange GRX (13). 

Orange GS (88). 

Orange GT (43). 

Orange M (88). 

Orange MN (95). 

Orange N (43,88). 

Orange O 27 (85). 

Orange O (43). 

Orange R (15, 55, 97). 

Orange RN (43). 

Orange RZ (85). 

Orange T (97). 

Orange 2 R (97). 

Orange Y (86). 

Orcellin No. 4 (102). 

Paris Violet (451). 

Phenylene Brown (197). 

Philadelphia Yellow G (532). 

Phloxin(521). 

PhloxinTA(521). 

Phosphin (532). 

Picric Acid (1). 

Pistachio (435). 

Polychromin (659). 

Pomona Green (459). 

Ponceau B (163). 

Ponceau 4 GB (13). 

Ponceau 4 RB (160). 

Ponceau G and GR (55). 

Ponceau R (55). 

Ponceau 3 RB (163). 



152 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



Ponceau 2 G (15). 

Ponceau 2 R (55). 

Ponceau 6 RB (169). 

Primula (450). 

Primulin (659). 

Printing Blue (599). 

Pure Soluble Blue (480). 

Pyoctanin Aureum (425). 

Pyoctanin (451). 

PjTosin B (517). 

Pyrosin J (516). 

Quinolin Yellow, water-soluble (667). 

Quinolin Yellow (667). 

Rauracienne (102). 

Red (107). 

Red Violet 5 R extra (450). 

Resorcin Yellow (84). 

Resorcein 275 (84). 

Rhodamin (504). 

Rhodamin B (504). 

Rhodamin O (504). 

Rhodamin B extra (504). 

Rhodamin G and G extra (502). 

Roccellin (102). 

Rose Bengal (520). 

Rose Bengal AT (520). 

Rose Bengal G (520). 

Rose Bengal N (520). 

Rosein (448). 

Rosolic acid (483). 

Rubianite (448). 

Rubidin (102). 

Rubin (448). 

Rubin S (462). 

Russian Green (394). 

Saffron Substitute (2). 

Saffron Yellow (3, 4). 

Safranilin (504). 

Safranin (584). 

Safranin AG, AGT, and OOF. (584). 

Safranin Cone. (584). 

Safranin extra G (584). 

Safranin FF extra (584). 

Safranin GOO. (584). 

Safranin S. (584). 

Safranin SP. (584). 

Safranin T. (584). 

Scarlet (55). 

Scariet L. (106). 

Sloelin (600). 

Sloelin RS. and BS. (601). 

Solferino (448). 

Solid Yellow (4). 

Soluble Blue (480j. 

Spirit Black (600). 



Spirit Blue (457). 

Soluble Blue 8 B. (479) 

Soluble Blue 10 B. (479). 

Soluble Blue XL. (479). 

Succinic (4). 

Sudan I (11). 

Sudan Red (614). 

Sulphin (659). 

Sulphin Yellow (4). 

Sulphonaphthol Acid Yellow (4), 

Sultan Red 4 B. (277). 

Sun Yellow (399). 

Tartrazin (94). 

ThioCatechin (675). 

Thio Catechin S. (675). 

Toluidin Blue O. (654). 

Tropeeolin D. (87). 

TropseolinG. (95). 

Trop^olin O (84). 

Tropseolin 00 (88). 

Trop^eolin 000 (85). 

Tropgeoiin 000 No. 2 (86). 

Tropseolin R (84), 

Ursol D. (574). 

Ursol DD. (574). 

Ursol P. (574). 

Vert Diamant (427). 

Vert Lumiere (459). 

Vesuvin (197). 

VesuvinB. (201). 

Victoria Blue B. (488). 

Victoria Blue 4 R. (490). 

Victoria Orange (2). 

Victoria Yellow (2). 

Victoria Yellow Cone. Z. (95). 

Vidal Black (670). 

Vidal Blacks. (670). 

Violein (593). 

Violet de Methylanilin (451). 

Violet R. (450). 

Violet RR. (450). 

Violet 5 R. (450). 

Water Black (166). 

Water Blue 6 B extra (480). 

Water Blue (480). 

Xanthin (532). 

XL Soluble Blue (479). 

Xylidin Red (55). 

Xylidin Scarlet (55). 

Yellow Corallin (483). 

Yellow FY. (4). 

Yellow MXX Cone. (95). 

Yellow W (9). 

Yellow WR. (89). 



DOSAGE AND SYMPTOMS. 153 

X. DOSAGE AND SYMPTOMS. 
CONFECTIONERS' LIST AS A BASIS FOR A RULE. 

Considering the Confectioners' List of 1899 as a correct guide as to 
which colors are harmful and which are harmless, the attempt has 
been made to determine how far dosage and the corresponding 
physiological effects may serve as a guide in determining which colors, 
other than those enumerated in either portion of the Confectioners^ 
List, are harmful or harmless. (See p. 48.) 

To this end the available literature has been searched and classified, 
and wherever it was possible to arrive at any conclusion as to the 
actual dose or the average dose over a stated period of time, and the 
corresponding physiological observations, these data have been sepa- 
rated and brought together for the purpose of making comparisons 
and deductions therefrom. 

It was thought that the literature w^ould show that if a dog or other 
animal is killed by a certain given amount of color per 100 pounds of 
body weight of the animal that such color is alw^ays harmful; that if 
untoward effects, such as vomiting, diarrhea, weakness, and general 
depression, are caused by more than a certain weight of color per 100 
pounds body weight of the animal, such color is always regarded as 
harmless. 

The classification of the available literature and the conclusions 
therefrom are as follows : 

Of the 33 coal-tar colors listed as harmless in the Confectioners' 
List, 10, namely, G. T. 4, 9, 55, 65, 85, 103, 105, 107, 448, and 462, 
have been tested on humans, while the conclusion as to the remaining 
23 is reached by the effects observed on dogs alone. However, con- 
tradictory statements are recorded in the case of No. 9, and none of 
these tests was of long-continued duration, but, on the contrary, in 
many cases the time covered was exceedingly short, and the conclu- 
sions deduced are, therefore, not necessarily final nor correct. It 
should be further noted that Nos. 95 and 106, reported as nonpoi- 
sonous to humans, are in the harmful section of this Confectioners' 
List. • 

I. Those colors which produced no effect are as follows (the num- 
ber of grains given is the amount administered per 100 pounds body 
weight; where the data permitted, the number of days' duration of 
the experiment is also given: 

Grains. 

5. Brilliant Yellow S 532 

13. Ponceau 4 GB 113 

521. Phloxin 100 

521. Phloxin 300 



154 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

II. Those colors which in some cases produced no effect, and in 
others produced eiTects, are as follows: 

4. Naphthol Yellow S: 

395 grains produced diarrhea and no albuminuria. 
292 grains produced albuminuria. 

116 grains for 25 days produced no effect. 

25 grains for 2 weeks, on alternate days, produced no effect. 
8 and 9. Fast Yellow Y and R: 

173 grains for 3 weeks produced no effect. 

53 grains produced albuminuiia. 
55. Ponceau 2 R. 

582 grains killed. 

198 grains produced no effect. 
65. Fast RedB: 

143 grains for 145 days produced no effect. 

137 grains for 145 days produced no effect. 

98 grains for 145 days produced no effect. 

68 grains produced albuminuria. 

38 grains produced albuminuria. 
103, Azorubin S: 

143 grains for 145 days produced no effect. 

137 grains for 145 days produced no effect. 

98 grains for 145 days produced no effect. 

70 grains produced diaixhea. 
287. AzoBlue: 

233 grains produced no effect. 

166 grains produced albuminuria. 

III. Those that produced only a slight disturbance which was 
regarded as negligible: 

28. Archil Substitute V: 

301 gi-ains produced vomiting and albuminuria. 

127 grains produced vomiting and albuminuria. 
105. Fast Red E: 

70 gi'ains produced diarrhea. 
166. Wool Black: 

117 grains produced albuminuria. 
240. Congo Red: 

192 grains produced albuminuria. 
269. ChrysaminR: 

433 grains produced albuminuria. 

361 grains produced albuminuria. • 

394. Dinitrosoresorcin : 

139 grains produced loss of appetite. 

121 grains produced albuminuria. 

From Class I above it would appear — 

(a) That if a dose of 113 grains per 100 pounds body weight pro- 
duced no effect it is to be classed as harmless. 

From Class II above it would appear — 

(a) That if albuminuria is caused by as little as 38 grains in some 
cases, and no effect is produced by doses as large as 143 grains, the 
?olor is to be classed as harmless. 



DOSAGE AND SYMPTOMS. 155 

(6) Also that if 198 grains produce no effect the color is to be 
classed as harmless, even if 582 grains in another case kill the animal. 

(c) That if small amounts produce albuminuria and larger amounts 
do not the color is to be classed as harmless. 

{d) That if small amounts produce diarrhea and larger amounts 
do not the color is to be classed as harmless. 

From Class III it would appear that — 

(a) Albuminuria produced by as little as 117 grains is to be regarded 
as not harmful. 

(Jb) Diarrhea produced by 70 grains is to be regarded as not harmful. 

(c) Vomiting and albuminuria produced by 127 grains are to be 
regarded as not harmful. 

The colors classed as harmful in the Confectioners' List may be 
classified as f oUows : 

I. Do^s.— Those colors that under certain conditions produce no 
noticeable effects on dogs, while under other conditions effects are 
observed, are classed as harmful colors: 

1. Picric Acid: 

Dogs stand 5 grains daily for 18 days without effect. 
18^ grains produced diarrhea. 
20.4 grains killed. 

2. Dinitrocresol: 

140 grains caused vomiting but did not kill. 
38^ grains caused vomiting but did not kill. 
38^ grains caused vomiting and did kill. 

35 grains caused vomiting but did not kill. 
31.6 grains caused vomiting but did not kill. 

3. Martins Yellow: 

51 grains do not kill, but produce weakness, diarrhea, and albuminuria. 
50 grains kill. 

8 grains do not kill, but produce weakness, diarrhea, and albuminuria. 
86. Orange II: 

714 grains produced kidney irritation, thirst, and diarrhea. 
333 grains kill, and produced diarrhea and albuminuria. 
244 grains produced kidney irritation, thirst, and diarrhea. 

36 grains produced no effect. 
95. Metanil Yellow: 

620 grains produce vomiting. 
603 grains kill. 
407 grains no effect. 
371 grains kill. 

104 grains produced albuminuria. 
62 grains no effect. 
41 grains no effect. 
31 grains kill. 
197. Bismarck Brown: 

246 grains produced vomiting. 

]18 grains produced vomiting and general depression. 

38^ grains daily for 30 days, no effect. 



156 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

398. Naphthol Green B: 

600 grains produced green urine and conjunctiva. 

292 grains produced no effect. 

128 grains produced green urine and conjunctiva. 

II. Those colors that have not been observed to give negative 
results, but which have caused certain effects : 

11. Sudan I: 

118 grains produced colored urine, vomiting, and albuminuria. 
17 and 18. Chrysoidin Y and R: 

79 grains produced albuminuria. 

74 grains for 30 days produced no albuminuria, but a loss of 12^ per cent of 
body weight. 
88. Diphenylamin Orange: 

216 grains produced albuminuria. 

128 grains produced phenol in urine and albuminuria. 
138. Fast Brown G: 

237 grains produced diarrhea and loss of appetite. 

218 grains produced diarrhea. 

III. Rahhits: 

1. Picric Acid: 

24.5 grains for 90 days, no effect. 

45 grains lor 19 days kill. 
86. Orange II: . . 

292 grains, no effect. 

933 grains kill. 
95. Metanil Yellow: 

216 grains, no effect. 

rV. Humans: 

1. Picric Acid: 

8.3 grains no effect. 
13.8 grains no effect. 
Invalids and children can not stand this color. 

2. Dinitrocresol: 

42 grains kill. 
86. Orange II: 

1^ grains, no effect. 

3 grains, headache, vertigo, dryness of throat, and poor general condition. ■ 
95. Metanil Yellow: 

1^ grains, no effect. 

3 grains, no effect. 

From Classes I and II above, it would seem to appear — 

(a) That if a dog is killed the color is harmful, even though it take as much as 603 
grains, or as little as 20.4 grains per 100 pounds body weight to kill. 

(6) That if albuminuria is produced in dogs by as little as 79 grains, or as much as 
128 grains, the color is harmful. 

(c) That if diarrhea is produced in dogs by as much as 218 grains, or as little as 50 
grains, the color is harmful. 

(d) That even if a dog can take as much as 407 grains, the color may be harmful. 



DOSAGE AND SYMPTOMS. 157 

From Class III it would appear — 

(a) That even if rabbits can stand as much as 292 grains, or as little as 24.5 grains, 
the color is harmful. 

From Class IV it would appear — 

(a) That if 42 grains kill a human, the color is harmful. 

(6) That even if humans can stand as much as 3 grains without untoward effect, 
the color is harmful. 

The conclusions that may be dra^^ai from these data are: 

1. If a dog is killed by — 

(a) 603 grains per 100 pounds body weight, the color may be harmful. 
(6) 582 grains per 100 pounds body weight, the color may be harmless. 

2. If a dog can bear without effect — 

(a) 407 grains per 100 pounds body weight, the color may be harmful. 
(6) 198 grains per 100 pounds body weight, the color may be harmless. 

3. If albuminuria is produced in a dog by — 

(a) 38 grains, or 143 grains per 100 pounds, body weight the color may be harm- 
less. 

(6) 79 grains, or 128 grains per 100 pounds body weight, the color may be harm- 
ful. 

4. If diarrhea is produced in a dog by — 

(a) 70 grains per 100 pounds body weight, the color may be harmless. 
(6) 50 grains per 100 pounds body weight, the color may be harmful. 

5. If vomiting and albuminuria are produced in a dog by 127 grains per 100 pounds 
body weight, the color is not necessarily harmful. 

6. If small amounts of color produce in a dog diarrhea or albuminuria, and larger 
amounts do not, the color may be harmless. 

7. Even though rabbits can withstand 292 grains per 100 pounds body weight, the 
color is not necessarily harmless, but may be harmful. 

8. If 42 grains kill a human, the color is harmful. 

9. If a human can withstand 3 grains without effect the color is not necessarily 
harmless, but may be harmful. 

10. If a human can not withstand 3 grains, even though it can withstand IJ grains, 
the color is not necessarily harmless, but may be harmful. 

Lehmann (Methoden der praMischen Hygiene, 1890, p. 54o) says: 

I regard such substances as harmful to health which when fed to a sound dog in 
doses of a few decigrams per day produce at once, or after a few repetitions of the dose, 
distiu-bances in the health of the dog; on the other hand, dyes which in doses of from 
one to several grams can be taken for weeks on end without causing any disturbance 
or only slight intestinal disturbances or a slight and passing albuminuria can be 
regarded as harmless. It should never be forgotten that a few milligrams of a coal- 
tar color dyes very strongly and it is not easy — even by most extraordinary use of 
colored objects, e. g., by children — that more than milligrams, at most centigrams, 
of dye can be introduced into the human stomach. In extremely large doses many 
substances, for example, all our condiments, are naturally harmful. 

Of 65 dogs weighed and experimented on by Chlopin the average 
weight was 9.2 kilograms, or 20.3 pounds; almost half the dogs (30) 
weighed between 6 and 11 kilos. 

To adapt the rules of Lehmann to a basis of grains per 100 pounds of 
body weight, assuming the average weight of a dog to be 20 pounds, 



158 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

it is only necessary to multiply the weight of color by 5 and by 
15.432. Doing so, the following data are obtained: 

A. Harmful colors produce bad e fects in doses of a *'few" decigrams, i. e., mul- 
tiples of a half gram; the word "few" is not sharply defined, but the rule means a 
"few" times 7.7 grains. 

B. Harmless colors produce, when continuously fed, no bad effect in multiples of 
10 of the doses of A, above, i. e., multiples of 77 grains. 

C. Slight diarrhea and slight, temporary albuminuria are not to count against the 
color. 

Appl3T.ng these rules to the preceding colors discloses that they were 
apparently not so used, in selecting the harmless and harmful colors 
in the Confectioners' List. 

LEHM ANN'S RULES. 

The Lehmann rules as just interpreted were applied to the data 
just given. As a result of such application the conclusion is reached 
that of the 15 colors classed as harmless (foregoing classes I, II, and 
III), 6 would be classed as doubtful by the Lehmann rules, namely: 

13. Ponceau 4 GB, 65. Fast Red B, 

8 and 9. Fast Yellow Y and R, 103. Azorubin S, 

55. Ponceau 2R, 105. Fast Red E, 

and the remaining 9 would have been classed as harmless. 

Of the 11 classed as harmful (foregoing classes I, II, III, and IV), 

2 would have been regarded as harmless, namely: 

398. Naphthol Green B, 138. Fast Brown G, 

3 would have been classed as doubtful, namely: 

197. Bismarck Brown, 88. Diphenylamin Orange, 

11. Sudani, 

and the remaining 6 would have been classed as harmful. 
SANTORI'S WORK AS A GUIDE TO A RT7LE. 

Santori regards the following six dyes as harmless: 457 (188), 
467 (74), 477 (129.5), 480 (156), 599 (64), 692 (467). 

The first is the Green Table number and the bracketed figure the 
average number of grains per 100 pounds per day for 30 days. 

In the case of Nos. 457 and 599 the animal was wholly normal 
throughout the test and the autopsy showed only normal conditions. 

In the case of No. 477 the only disturbance wis colored feces and 
the autopsy showed only normal conditions. 

In the case of No. 480 the only disturbance was colored feces, but 
the autopsy showed a pea-green kidney. 

In the case of Nos. 467 and 692 there was only vomiting; in the 
case of No. 467 tlie autopsy showed cveiything normal; whereas in the 
case of No. 692 the autopsy disclosed a swollen kidney. 

Therefore, according to Santori, a dye that causes colored feces, 
even with colored kidney, is harmless. Also a dye that causes vomit- 



OIL-SOLUBLE OE FAT COLORS. 159 

ing and swollen kidney is harmless. On the other hand, a dye (572) 
which produces no change or symptom observable during life, but 
fatty degeneration of the liver is shown, at the autopsy, is a harmful 
dye. This lack of conformity makes the relation between dosage, 
symptoms, and harmfulness or harmlessness more confusing and per- 
plexing. 

YOUNG'S RULE. 

It must be remembered that smaller amounts of drugs, and, there- 
fore, of coal tar colors, effect children as a rule than are effective 
upon adults. Taking Young's rule as a guide, it appears that gen- 
erally the effective dose for a 3-year-old child is one-fifth the effec- 
tive adult dose; for a 4-year-old child one-fourth; for a 6-year-old 
child one-third; for an 8-year-old child two-fifths and for a 12-year- 
old child one-half the effective adult dose. All of this should be taken 
into account in drawing conclusions from experiments as to the harm- 
lessness of any coal-tar dye upon humans. Very little attention has, 
however, been paid to this aspect of the matter in spite of the fact 
that colored foods, confectionery, pastry, beverages, and the Uke are 
partaken of by children and in many cases such articles are prepared 
for the sole or particular consumption of the very young. 

From the foregoing data it seems clear that deductions as to the 
harmlessness or harmfulness of coal-tar dyes when administered to 
dogs, and not based upon autopsies, are not final nor conclusive as to 
the effect upon the dog. The extent to which such deductions are 
correctly transferable to humans is likewise not established. 

XI. OIL-SOLUBLE OR FAT COLORS. 

Oil-soluble colors are used for coloring fats, such as butter, oleo- 
margarine, edible oils, and the like; of the coal-tar colors the oil- 
soluble colors are chemically nonsulphonated azo-colors. 

The nonsulphonated azo-colors which have been physiologicallj 
examined are: 

11. Sudan I (anilinazo-b-naphthol) (2). 

16. Butter Yellow (anilin-azo-dimetliylamliii). 

17. Clirysoidin Y (anilin-azo-m-phenylene-diamin) (2). 

18. Chrysoidin R (anilinazo-m-tolylene-diamin) (1). 
41. Clirysoidin R (o-toluidin-azo-m-tolylene-diamin). 

197. Bismarck Brown (m-phenylene-diamin-disazo-m-phenylene-diamin) (4). 
201. Manchester Brown (m-tolylene-diamin-disazo-m-tolylene-diamin) (2). 

The numbers preceding the trade names are the Green Table num- 
bers; the scientific names appear in parentheses; and the number of 
dealers offering the colors on the United States market in the summer 
of 1907, out of a possible 12, appear after the scientific name, also in 
parentheses. 



160 COAL-TAR COLOES USED IN FOOD PRODUCTS. 

For all but No. 201 contradictory statements occur in the compiled 
literature; for No. 201 only unfavorable reports were found. 

There were on the United States market in the summer of 1907 the 
following oil-soluble colors : 

10. Sudan G (anilin-azo-resorcin) (1). 

11. Sudan I (anilin-azo-b-naphthol) (2). 

49. Sudan II (xylidin-azo-b-naphthol) (1), 

60. Carminaph Garnet (a-naphthylamin-azo-b-naphthol) (1), 

Of these No. 11 had been reported on contradictorily, and the 
remaining three had not been reported on at all. In addition to these 
the following three oil-soluble colors, not listed in the Green Tables 
and not reported on in literature, were wanted: 

1. o-Toluidin-azo-b-naphthylamin (which does not seem to be described in litera- 
ture in any way). 

2. Amidoazo-toluol. 

3. Anilin-azo-b-naphthylamin. 

So that out of a total of seven oil-soluble colors on the United 
States market in the summer of 1907 only one had been examined 
physiologically and that with contradictory results. As before 
stated, these oil-soluble colors all belong to the class of nonsulpho- 
nated azo-colors. 

Fraenkel (p. 575) says: "When, however, the azo-colors contain 
no sulpho-group (i. e., are nonsulphonated) they are poisonous. 
Thus for example, Bismarck Brown * * * Sudan 1.'' Yet 
meta-nitrazotin, a nonsulphonated color not in the Green Tables, 
and probably not upon the market anywhere, and which is meta- 
nitranilin-azo-b-naphthol, is according to Weyl nonpoisonous. 

Fraenkel (p. 575) also stated: 

The fact that the monazo colors examined by Cazeneuve and Lepine are harmless, 
as above stated, is equally explained by the constitution of these substances. Those 
two investigators examined (omitting the trade names) a-naphthylamin-sulphoacid- 
azo-a-naphthol-a-sulphoacid, a-naphthylamin-sulphoacid- azo - b - naphthol - disulpho- 
acid, a-naphthylamin-azo-b-naphthol-disulphoacid, xylidin-azo-b-naphthol-disulpho- 
acid, sulphanilicacid-azo-a-naphthol, Amido-azo-toluene-disulphonicacid. 

These substances are all sulphoacids and the sulpho-groups here effect the depoison- 
ing of the original substance. 

Examining this statement it therefore appears that in Fraenkel's 
opinion, at least, a-naphthylamin-azo-a-naphthol, a-naphthylamin- 
azo-b-naphthol, xylidin-azo-b-naphthol, anilin-azo-a-naphthol, and 
amido-azo-toluol are in and of themselves poisonous substances, and 
are rendered nonpoisonous by sulphonation. Diligent search tlirough 
the literature has failed to uncover any original communications of 
investigators to that effect. 

With but one known exception all the nonsulphonated azo-colors 
are regarded by Fraenkel as poisonous. The colors 17, 18, 41, 197, 
and 201 on page 159 are not used as oil-soluble colors and therefore 
form no comparative basis for judging oil-soluble colors except that 



REASONS FOR SELECTING SEVEN PERMITTED COLORS. 161 

both are nonsulplionated azo-colors; in FraenkeFs opinion, however, 
such a comparison is wholly justified and proper. 

Excluding now 17, 18, 41, 197, and 201 for the purposes of com- 
parison, the following tabulation is made: 

Oil-soluble nonsulphonated azo-colors on the market, 1907, deemed poisonous by Fraenhel. 

On United Fraenkel 
Oil-soluble colors. States calls 

narket. poisonous. 



anilin-azo-resorcin 

anilin-azo-b-naphthol 

xylidin-azo-b-naphthol 

a-naphthyiamin-azo-b-naphthol . 
o-toluidin-azo-b-napbthylamin. . 

amido-azo-toluol 

anilin-azo-b-naphthylamin 

a-naphthylamin-azo-a-naphthol . 
aniUn-azo-a-naphthol 



That is, the only ones on the United States market concerning 
which no expression of specific opinion is to be found in Fraenkel are 
the following three: anilin-azo-resorcin, toluidin-azo-b-naphthylamin, 
and anilin-azo-b-naphthylamin, and nothing is published on the 
physiological action of any of them specifically. The probability, 
however, would seem to be that they are not harmless, and until 
their harmlessness is positively established their exclusion from the 
permitted list of coal-tar colors for use in foods seems to be the only 
safe and proper course to be followed. The physiological action of 
so-called ''Butter Yellow" No. 16 of the Green Tables (see p. 85), 
merely strengthens this conclusion. 

XII. RULES AND REASONS FOR SELECTING THE SEVEN COLORS 
PERMITTED BY F. I. D. 76. 

STATEMENT OF RULES. 

In view of the confusion and uncertainty disclosed in the foregoing 
Hterature relative to the physiological action of coal-tar colors, the 
difficulties in the way of making a Hst of coal-tar colors to be 
permitted in the coloring of food products are seen to be by no 
means shght. The following rules governing selection were in mind 
during the making of the list given in Food Inspection Decision No. 76, 
and the closeness with which they were followed is discussed on 
page 166. 

Rule I. All colors which have not been physiologically tested either 
upon animals or man shall not be permitted for use in foods. 

Rule II. AU coal-tar colors which have been examined physio- 
logically with contradictory results shall not be permitted for use in 
foods. 

97291°— Bull. 147—12 11 



162 



COAL-TAK COLORS USED IN FOOD PRODUCTS. 



Rule III. All coal-tar colors which have been examined physiologi- 
cally and have been declared to be of doubtful harmlessness shall not 
be permitted for use in foods. 

Rule IV. Only those coal-tar colors whose chemical composition 
was definitely disclosed or otherwise ascertained, and wliich were on 
the United States market in the summer of 1907, and wliich have 
been examined physiologically and with no other than a favorable 
result shall, for the present, be permitted for use in foods. 

ANALYSIS OF THREE RECOMMENDATIONS MADE TO THE DEPART- 
MENT OF AGRICULTURE. 

These rules were formulated as a guide in view of the divergent 
opinions expressed in three diiferent recommendations to the Depart- 
ment of Agriculture. One of these recommendations suggested that 
permitted colors be designated by nine titles. Comparison of these 
titles with the Green Tables and with the tabulated survey of the unfa- 
vorable, favorable, and contradictory literature corresponding to the 
Green Table numbers (p. 63) discloses the following facts: 

Comparison of nine suggested color titles with corresponding Green Table numbers and 

the reports on the same. 



Name. 


Green 

Table 

No. 


Un- 
favor- 
able. 


Fa- 
vor- 
able. 


Con- 
tra- 
dic- 

tory. 


No 
re- 
port.! 


Name. 


Green 

Table 

No. 


Un- 
favor- 
able. 


Fa- 
vor- 
able. 


Con- 
tra- 
dic- 
tory. 


No 

re- 

port.i 


Chrysoidin 


17 
18 
41 
84 
85 
86 
87 
88 
95 
92 
102 
13 
15 
4-1 
55 
66 
57 
108 
114 
146 






X 
X 
X 
X 




Ponceau 


147 
148 
150 
160 
163 
169 

65 
107 
157 
170 
171 
198 
244 

20 

462 
4 














Bordeaux 








X 
















Tropseolin 










X 
X 






X 










X 
X 
X 

X 






x 

X 
X 




















BiebricliRed(?).. 
Sulphonaled 
Fuchsin 














X 






X 

X 










Roccellin 












X 




X 
X 


X 

X 
X 
X 
X 
X 




































X 








X 




X 
X 






















Naphlhol Yellow 
























Total 




. 












36 





8 


13 


15 













1 Of physiological tests in literature compiled. 

Therefore, under 9 titles 36 di.Terent chemical individuals would 
be placed upon the permitted list, of which only 8, or less than 25 per 
cent, have been examined physiologically ^vith only favorable 
results, and 28, or more than 75 per cent, had either not been examined 
at all physiologically or with contradictory results. 



REASONS FOR SELECTING SEVEN PERMITTED COLORS. 



163 



The 8 of these chemical individuals examined with only favorable 
results, and the number of sources out of a possible 12 oiTering them 
on the United States market in the summer of 1907, are as follows: 

Colors reported on favorably and number of dealers handling same. 



Green 

Table 

No. 


Sources 
ofEering, 


Green 

Table 

No. 


Sources 
offering. 


05 
85 
92 


10 
2 
2 



102 
107 
169 
462 




7 
1 
2 



1 The italicized Green Table numbers are those of the permitted list of Food Inspection Decision No. 76. 

Another recommendation suggested the permissive use of 42 
entries in the Green Tables, which are tabulated below in the same 
manner as the suggestions in the preceding recommendation: 

Comparison of 42 recommended Green Table numbers with reports in the literature. 



Green 
table 
No. 


Un- 
favor- 
able. 


Favor- 
able. 


Equiv- 
ocal. 


No 
report.i 


Green 
table 
No. 


Un- 
favor- 
able. 


Favor- 
able. 


Equiv- 
ocal. 


No 

report.i 


17 
50 
53 
54 
55 
65 
85 
86 
89 
92 
94 
102 
103 
107 
138 
163 
166 
240 
269 
2S7 


... 


X 




1 


427 
434 
448 
451 
456 
457 
462 
477 
478 
479 
480 
504 
512 
513 
514 
516 
617 
618 
562 
601 

Total 






X 





X 
X 


X 
X 

X 


X 










X 
X 


X 






























X 






X 


X 
X 


X 
X 




X 
X 














X 










X 


X 
X 




X 
X 


















X 


X 
X 

X 








X 
X 
















X 






X 
X 




X 












X 

X 




X 
X 
















X 


X 
X 












5 


14 


15 


8 







1 Of physiological tests in compiled literature. 

Applying the conclusions hereinbefore reached to these entries, 
it is found that 14 out of the 42 colors recommended, or exactly 
one-third, had been examined physiologically with only favorable 
results, and the remaining two-thirds had been either examined 
physiologically with only unfavorable or with conflicting results, 
or had not been examined at all. 

The 14 chemical individuals examined with favorable result and 
the number of sources out of a possible 12 offering them on the 
United States market in the summer of 1907 are as follows: 



164 COAL-TAE COLORS USED IN FOOD PRODUCTS, 

Colors reported on favorably and number of dealers handling same. 



Green 
table 
No. 


Sources 
ofiering. 


Green 
table 
No. 


Sources 
offering. 


65 
85 
89 
92 
102 
103 


10 
2 
2 
1 


6 


107 
166 
240 
462 
477 
512 
577 


7 

1 
2 

3 
5 



» The Italicized Green Table numbers are those of the permitted list of Food Inspection Decision No. 76. 

The third of these recommendations suggested 27 different chemical 
individuals for permissive use; these are tabulated below in the same 
manner as the suggestions in the preceding recommendations. 

Twenty-seven colors recommended for use and reports in the literature on the same. 



Green 
table 
No. 


Un- 
favor- 
able. 


Favor- 
able. 


Equiv- 
ocal. 


No 
report.i 


Green 
table 
No. 


Un- 

favor- 
able. 


Favor- 
able. 


Equiv- 
ocal. 


No 
report.' 


4 

16 

17 

18 

41 

65 

85 

102 

197 

201 

398 

457 

462 

476 

477 




X 






481 
512 
516 
517 
518 
521 
532 
584 
601 
602 
650 
692 

Total 








X 


X 
X 
X 
X 




X 


X 
















X 












X 




X 
X 
X 


X 


X 


















X 
X 




X 








X 




X 






X 
X 






X 











X 




X 








X 


4 


10 


10 


3 




X 









1 Of physiological tests in literature compiled. 

Therefore, applying the same method of drawing conclusions as 
in the case of the preceding two recommendations, it appears that 
10 out of the 27 suggested chemical individuals had been examined 
physiologically with only favorable results, and the remaining 17 
had either not been examined at all or with unfavorable or con- 
flicting results. The 1 chemical individuals examined with favorable 
results, and the number of sources out of a possible 12 offering them 
on the United States market in the summer of 1907, are as follows: 

The 10 recommended colors favorably reported on in the literature and the dealers handling 

same. 



Green 


Sources 


Green 


Sources 


Table 


han- 


Table 


han- 


No. 


dling. 


No. 


dling. 


M 


10 


477 





65 


2 


512 


3 


85 


2 


617 


5 


102 





521 





462 


2 


692 


3 



> The italicized Green Table numbers are those of the permitted list of Food Inspection Decision No. 76. 



BEASONS FOR SELECTING SEVEN PERMITTED COLORS. 



165 



All of the colors included in these three recommendations con- 
cerning which only favorable reports were found in the literature are 
given in the following table : 

Recommended colors favorably reported on in the literature. 





Recommendations. 






Recommendations. 




Green 






Dealers 


Green 






Dealers 


Table 






offer- 


Table 






offer- 


















No. 


I- 


II. 


III. 


Total. 


ing. 


No. 


I. 


II. 


III. 


Total. 


ing. 


M 


X 


X 


X 


3 


10 


240 




X 




1 


1 


65 


X 


X 


X 


3 


2 


462 


X 


X 


X 


3 


2 


85 


X 


X 


X 


3 


2 


477 




X 


X 


2 





89 





X 




1 


1 


512 




X 


X 


2 


3 


92 


X 


X 




2 





617 




X 


X 


2 


5 


102 


X 


X 


X 


3 





521 






X 


1 





103 








1 


6 


692 








1 


3 


\107 


X 


X 




2 


7 
























166 
169 


X 


X 




1 

1 




1 


Total . 


8 


14 


10 















1 The italicized Green Table numbers are those of the permitted list of Food Inspection Decision No. 76, 

This table is now rearranged to show — 
I. The recomm£nded colors not offered in the United States market in the summer of 1907. 



Green 
Table No. 


Recom- 
mended 
by- 


Green 
Table No. 


Recom- 
mended 
by- 


92 
102 
166 


2 
3 

1 


477 
521 


2 
1 



II. The recommended colors offered on the United States market in the summer of 1907. 



Green 
Table No. 


Recom- 
mended 
by- 


Som-ces 
handling. 


Green 
Table No. 


Recom- 
mended 
by- 


Sources 
handling. 


65 
85 
89 
103 
107 


3 
3 
3 

1 
1 
2 


10 
2 
2 

1 


169 
240 
462 
512 
517 
692 


1 
1 
3 
2 
2 
1 


1 
1 
2 
3 
5 
3 



1 The italicized Green Table numbers are those of the permitted list of Food Inspection Decision No. 76. 

It appears that out of 17 different chemical individuals suggested 
by these 3 recommendations jointly, 5 were not on the United States 
market in the summer of 1907, and 12 were on that market; also that 
of these 12, 4 were suggested by all 3 recommendations; 3 were 
wanted by only 2 out of the 3, and the remaining 5 were spoken for 
by only one. Examining all of the recommendations, it appears 
that out of a total of 79 recommendations 17 had been examined with 
only favorable results, and that the remaining 62 were either not 
examined or had been examined with unfavorable or conflicting 
results. 

To add to the confusion the third recommendation mentioned sug- 
gested that the following Green Table nurabers should not be permit- 



166 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

ted for use in food products because they are harmful : 1; 2; 3; 6; 86; 
95; 425; 451; 454; 480; 483; 484; 487; 488; 490; 571; 584; 599; 
620; 624; 650. The same paper, however, recommended that Nos. 
584 and 650 be permitted for use in food products; that No. 86, sug- 
gested by both the other recommendations, be prohibited; and that 
Nos. 95, 451, and 480, suggested by one or the other of the remaining 
two recommendations, be Hkewise prohibited for use in food products. 
It must be clear to everyone that these three recommendations are 
not of one mind as to (1) the colors which are harmless; (2) the 
colors which are harmful; (3) tho colors which are used or are useful 
in food coloring; and (4) the colors which should be used in food 
coloring. Such a state of affairs fully justifies rules of the scope and 
intent of those formulated at the beginning of this section for making 
a selection of permissible food colors. 

PROCESS OF ELOIINATIOISr. 

From the foregoing data it appears that out of 80 different chemical 
individuals on the food-color market of the United States in 1907, 
only 16 had been examined physiologically with a favorable result 
(see p. 64). 

These 16, arranged according to the shade produced, are as follows 
(numbers preceding the names are the Green Table numbers; the 
numbers in parentheses show the number of sources desiring the color; 
the italicized Green Table numbers are the ones finally selected by 
Food Inspection Decision No. 76): 

REDS, 

65. Fast Red B (Alphanaphthylamin azo-R-salt) (2). 
103, Azorubin S (Naphthionic acid azo NW acid) (6), 
105, Fast Red E (Naphthionic acid azo-Schaeffer acid) (1). 
107. Amaranth (Naphthionic acid azo-R-salt) (7). 

169. Crocein Scarlet 7B (Amidoazotolutol-monosulphonic-acid-azo-betanaphthol- 
monosulphonic acid B) (1). 

240. Congo Red (Benzidin disazo-naphthionic acid) (1). 

462. Acid Magenta (Magenta trisulphonic acid) (2). 

512. Eosin A (Tetra-bromo-fiuorescein) (3). 

517. Erythrosin (Tetra-iodo-fluorescein) (5). 

520. Rose Bengal (Dichlor-tetraiodo-fluorescein) (2). 

ORANGE. 

85. Orange I (Sulphanilic acid azo-alpha-naphthol) (2). 

YELLOWS. 

4. Naphthol Yellow (Dinitroalphanaphtholsulpho acid) (10). 
89. Brilliant Yellow S (Sulphanilic acid azo-diphenylamin, sulphonated) (1). 

GREENS. 

433. Guinea Green B (Benzyldehyde -|- benzylethyanilin sulpho-acid) (1). 
435. Light Green S F yellowish (Benzyldehyde+benzylethylanilin-|-8ulphona- 
tion) (4), 



REASONS FOR SELECTING SEVEN PERMITTED COLORS. 167 



€9^. Indigo Carmine (Indigo disulpho acid) (3). 

Considering now the reds, and particularly 107, which, as the num- 
ber appearing in parentheses after the scientific name indicates, was 
wanted by 7 sources out of the 12 drawn on, this being the most 
desired of all the reds, it would seem reasonable to believe that all the 
wants supplied by 65, 103, 105, 169, 240, and 462 would be covered 
by 107. Chemically 107 is closely allied to 65, 103, 105, and tinc- 
torially it is likewise closely allied to 169, 240, and 462. 

Nos. 512, 517, and 520 are chemically quite different from the other 
members of this group, and tinctorially they differ, being of a particu- 
larly brilliant shade, and tinctorially more powerful; 517 being 
desired by 5 out of the 12 sources drawn upon, and thus being the 
most desired of these three colors, was selected in the expectation 
that any work 512 and 520 could do in food products would be equally 
well done by 517. For reds, therefore, the choice fell upon 107 and 
517. 

Orange. — Only one color was wanted, and that by 2 out of the 12 
sources, and this was placed in the permitted list. 

Yellows. — The choice of No. 4, which was wanted by 10 out of the 
12 sources, was made in the expectation that every purpose that 89 
could serve in food products could be served also by 4. 

Greens. — Tinctorially and chemically the two greens are very 
closely allied, and in view of the reasonableness of the expectation 
that 435 could do all the work of 433 as well, its choice was regarded 
as justified, especially as 435 was wanted by 4 out of the 12 sources, 
as against only one for 433. 

Blue. — No. 692 being regarded as harmless by all, and being the 
only blue in the list, it was selected. 

In this manner six out of the seven permitted colors were selected. 

REASONS FOR ADDING PONCEAU 3R. 

An examination of the table on page 20 discloses the fact that 
among the reds desired four were azo-reds made from anilin deriva- 
tives as the first component, namely: 

53. Xylidin-azo-alplianaphtholdisulpho acid. 

54. Xylidin-azo-Schaeffer acid, 

55. Xylidin-azo-R-salt. 

56. Cumidin azo-R-salt. 

Each of these was wanted by 1 source out of the possible 12. This 
was construed as an expression of a real need in the art of food coloring 
for a color of this class. The reason for such a need was not then, nor 
is it now, apparent, but the propriety of giving even a seeming need 
due consideration was regarded as justified. For only one of the four 
desired, namely, 55, could any specific references in the literature be 



168 COAL-TAE. COLORS USED IN FOOD PRODUCTS. 

found, and, in fact, four references were found favorable thereto and 
three unfavorable thereto; thus eliminating 55 from consideration, 
leaving 53, 54, and 56. 

The Austrian law of January 22, 1896 (see Lieber, "p, 15) ^ permits 
the use of azo colors derived from higher homologues of anihns, 
beginning with xylidin and sulphonated betanaphthols. As Nos. 53 
and 54 were both derived from xylidin, it was regarded as safe to 
assume that they would probably be as objectionable as 55. This 
left 56 only to be considered, which color is derived from cumidin 
and R-salt. The cumidin portion satisfies the Austrian law and also 
satisfies the general law laid down in Fraenkel (^„ 162), namely, that 
the greater the number of ring-methyls the less the toxic property of 
the resulting compound, because of the oxidation of these methyls to 
carboxyls in the animal system; the R-salt portion satisfies the gen- 
eral law laid down in Fraenkel, that the more highly sulphonated the 
less toxic a substance becomes, and therefore 56 is in the first portion 
of its composition of such a nature as to be less objectionable than 55, 
if 55 be objectionable. 

This combination of facts, namely, the desirability of an anilin 
azo-red, the provision for diminishing the toxicity of 55 by the sub- 
stitution of cumidin for xylidin therein, and the general provision 
in the Austrian food law, made it appear desirable and safe to take 
into account an anilin azo-red, and therefore to select 56 as probably 
the least objectionable, if it be at all objectionable, of the anilin 
azo-reds. 

The full list of permitted colors was therefore extended to 7, as 
follows : 

Red shades. — 107. Amaranth; 56. Ponceau 3R; 517. Erythrosin. 

Orange shade. — 85. Orange I. 

Yellow shade. — 4. Naphthol Yellow S. 

Green shade. — 435. Light Green S F yellowish. 

Blue shade. — 692. Indigo disulpho acid. 

It should be noted that with respect to tetra-iodo-fluorescein, 517 
of the Green Tables, no specific investigation, pronouncing it harmless 
or harmful, is described in the literature. No. 516, the diodo-fluores- 
cein, is reported specifically adversely in the literature, especially by 
Chlopin; the Confectioners' List, the laws of Austria, the laws of 
France, the rather superficial examination of No. 517 by Grandhomme, 
and the statement in Fraenkel {'p. ^74), that it produces no disturbance; 
are all taken to apply to 517 and not to 516. The identification of the 
color under examination with 517 has not in all cases been satisfac- 
torily exclusive, but it is believed that the differentiation of the 
harmful 516 by Chlopin makes all the other references cited pertinent 
to 517. 



LISTS OF COLORS RECOMMENDED BY INDIVIDUALS. 169 

With respect to 435, it must be pointed out that 434, which is the 
methyl instead of the ethyl derivative, has only been regarded as 
suspicious, and one examination of 435, namely, that of Lieber 
{p. 144) J <ioes not appear to disclose anything which would positively 
exclude 435. 

QUALITY, CLEANLINESS, AND EFFICIENCY. 

The justification for limiting the permitted colors to 6 out of 16, 
against which nothing unfavorable is contained in the literature and 
regarding which favorable statements are at hand, and the addition 
to these 6 of the seventh color is to be found in the very great variation 
in tinctorial quahty, in percentage of coloring matter, in amounts 
of insoluble matter, both organic and inorganic, and in the amounts 
of organic matter not coloring matter, as well as in the large number 
of samples containing an amount of arsenic in excess of that permitted 
by the United States Pharmacopoeia for the only coal-tar color 
therein mentioned, namely. Methylene Blue, and the varying amounts 
of heavy metals, such as copper, lead, and iron, mostly in excess of 
the hmits permitted in the Pharmacopoeia for various medicinal 
chemicals. This wide variation in quality and degree of cleanliness, 
all pointing to a very great dijfference in the care with which coal-tar- 
colors offered for food- purposes are prepared, render the conclusion 
safe that some control over food colors in respect to quahty is desir- 
able, necessary, and essential. 

The efficiency of the 7 colors, 6 of which were selected from among 
the 16 considered for the purpose of makiug this list of permitted colors 
as being reasonably sure to be harmless, is evidenced by the fact that, 
although the addition of colors has been sought by persons interested 
in the food-coloring art, not one of the remaining 10 colors of those 
16 has been so requested. In other words, the colors that the depart- 
ment has been requested to add to the permitted list were outside 
of the 16 colors which were on the markets of the United States in 
1907, and were described in the literature in such a manner as to lead 
to the conclusion that they were probably not harmful. 

XIII. LISTS OF COLORS SUBSEQUENTLY RECOMMENDED BY 
INDIVIDUALS AND ASSOCIATIONS. 

Since Food Inspection Decisions Nos. 76 and 77 were published 
recommendations of lists of permitted colors have been made by 
other individuals and by a voluntary association. For the purpose 
of comparing these proposed Hsts of permissible colors with the per- 
mitted list of Food Inspection Decision No. 76, the former are now 
to be examined in the same manner as the coal-tar colors, on the 
United States market in the summer of 1907 for food coloring pur- 



170 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



poses, were examined in order to establish the permitted list of 7 
colors. These recommendations cover the following lists : 

1. W. Ernst's list. 

2. Muttelet's interpretation of the French law. 

3. Second International White Cross Congress list. 

4. Beythien and Hempel's list. 

5. An American manufacturer's list. 

6. Behal's list. 



ERNST. 

W. Ernst (Fdrher Zeitung 1908, vol. 19, p. 381; abst. CTiem. Ztg. 
^' Reportorium" 1909, p. 89) recommends for use in foods the following 
38 titles of coal-tar colors. The Green Table numbers appear in 
parentheses after each title where corresponding numbers could be 
ascertained; the italicized numbers are those of the permitted hst 
of Food Inspection Decision No. 76. 

504, 



151, 



1. Auramin (425, 426). 




21. 


Rhodamin (496, 497, 498, 502, 


2. Naphthol Yellow S {4). 






505). 


3. Quinolin Yellow (666, 667). 




22. 


Acid Magenta (462). 


4. Tartrazin (94). 




23. 


Safranin (583, 584, 585). 


5. Acid Yellow (8, 88, 95, 4). 




24. 


The Croceins (13, 104, 106, 145, 


6. Spirit Yellow (Amidoazobenzol) (7). 




160, 164, 169). 


7. Curcumin S (399). 




25. 


Acid Green (434, 435). 


8. Eosin (512, 514, 515, 517, 521). 




26. 


Brilliant Fulling Green (?). 


9. Erythrosin (516, 517). 




27. 


Malachite Green (427, 428). 


10. Fluorescein (510). 




28. 


Brilliant Green (428). 


11. Orange II (86). 




29. 


Water Blue (480). 


12. Crocein Orange (13). 




30. 


Patent Blue (440, 442). 


13. Basic Oranges (?). 




31. 


Brilliant Fulling Blue (?). 


14. Fast Red (63, 65, 102, 103, 105, 


107, 


32. 


Domingo Blue B extra (?). 


144). 




33. 


Methyl Violet (451, 454). 


15. Amara Red (?). 




34. 


Acid Violet (464, 465, 467, 468, 


16. Naphthol Red (?). 






471, 472, 474, 507). 


17. Azo red (62). 




35. 


Bismarck Brown (197, 201). 


18. Bordeaux (65, 107, 157, 170, 171, 


198, 


36. 


Acid Brown (133, 138). 


244). 




37. 


Nigrosin (600,602). 


19. Victoria Rubin (?). 




38. 


Several Acid Blacks (184 and ?) 


20. Ponceau (13, 15, 44, 55, 56, 57, 


108, 






114, 146. 147, 148, 150, 160, 163 


169, 






448). 









470, 



Of these 38 titles only 11 refer to a single entry each in the Green 
Tables (namely 2, 4, 6, 7, 10, 11, 12, 17, 22, 28, 29); 7 titles can not 
be definitely connected with any entry in the Green Tables (titles 13 
15, 16, 19, 26, 31, 32); one title is broader than the corresponding 
color in the Green Tables (title 38) and the remaining 19 titles each 
and all refer to more than one entry in the Green Tables. 



LISTS OF COLOES RECOMMENDED BY INDIVIDUALS. 171 

These 31 titles embrace 88 different entries in the Green Tables; 
some of these entries are included in two or more titles as follows: 



Green Table 

number. Titles, 

4 2,5 

13 12,20,24 

65 14,18 

101 14,18 



Green Table 

number. Titles. 

160 20,24 

169 20,24 

428 27,28 

sn 8,9 



These 88 different Green Table entries can be divided as follows on 
the basis of the compilation of literature on physiological action here- 
inbefore given (see p. 63) : 

Unfavorable only —94:, 164, 201, 425, 434, 502, 516, 602, 667. Total 9, or 10.2 per 
cent. 

Favorable only.— 4, 65, 102, 103, 105, 107, 169, 399, 435, 462, 467, 512, 517, 521, 600. 
Total 15, or 17.0 per cent. 

Conflicting.—S, 13, 15, 55, 86, 88, 95, 106, 138, 160, 163, 197, 427, 428, 448, 451, 480, 
504, 584. Total 19, or 21.6 per cent. 

Not reported on.— 7, 44, 56 \ 57, 62, 63, 104, 108, 114, 133, 144, 145, 146, 147, 148, 
150, 151, 157, 170, 171, 184, 198, 244, 426, 440, 442, 454, 464, 465, 468, 470, 471, 472, 474, 
496, 497, 498, 505, 507, 510, 514, 515, 583, 585, 666. Total 45, or 51 per cent. 

According to this mode of judging only 15, or 17 per cent, of the 
colors suggested by Ernst for food coloring would be regarded as 
proper for use in foods. 

These 15 embrace 4 of the 7 permitted colors of Food Inspection 
Decision No. 76, namely, 4, 107, 435, and 517, leaving 11 to be con- 
sidered. Of these, 5 were not on the United States market in the 
summer of 1907, namely, 102, 399, 467, 521, and 600. 

The remaining 6 are as follows (the numbers in parentheses being 
the number of sources out of a possible 12 offering them on the United 
States market in the summer of 1907): 65 (2); 103 (6); 105 (1); 169 
(1); 462 (2); and 512 (3). 

The reasons for the noninclusion of these in the permitted list of 
Food Inspection Decision No. 76 have been given on page 167. 

MUTTELET'S INTERPBETATIOlSr OF THE FRENCH LAW, 

Muttelet {Annates des Falsifications, 1909, pp. 26-38), places the 
following interpretation on the French regulations of December 29, 
1890, and of August 4, 1908, classifying them as — 

I. Those colors which are certainly permitted by those regulations. 
" II. Those colors whose permitted or prohibited use is doubtful. 
III. Those colors which are certainly prohibited. 

The Green Table numbers contained in each class are classified as 
follows (the italicized numbers being those of the permitted list of 
Food Inspection Decision No. 76): (a) Unfavorably reported; (6) 

1 See page 107 for special reasons for including Ponceau 3R in permitted list. 



172 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

favorably reported; (c) conflictingly reported; {d) not reported in 
the literature as to their physiological action (see p. 63) ; in paren- 
theses is given the number of sources out of a possible 12 offering 
those colors on the United States market in the sunmaer of 1907. 

I. Those colors which are certainly permitted: 

(a) None. (6) 4 (10); 5 (0); 462 (2); 512 (3); 517 (5); 520 (2); 600 (0); total, 7. 
(c) 55 (2); 427 (2); 451 (5); 457 (0); total, 4. {d) 158 (0); 518 (2); total, 2. 

II. Those colors whose permitted or prohibited use is doubtful: 

(a) None. (6) 65 (2); 107 (7); 599 (0); total, 3. (c) 8 (5); 84 (2); 427 (2); 
457 (0); 601 (1); total, 4. {d) 452 (2); 456 (0); 513 (0); 514 (0); total, 4. 

III. Those colors which are certainly prohibited: 

(a) 3 (0); (6) none; (c) 427 (2); {d) none. 

It will be noted that 427 appears in all three of Muttelet's classifi- 
cations. The reason for this is that 427 is or has been marketed in at 
least three different forms; of these the straight chlorhydrate is per- 
mitted, the oxalate and the zinc chlorid double salt are of doubtful 
admissibiHty, and the picrate is undoubtedly forbidden. 

Also 457 appears in Muttelet's Classes I and II because the ''Bleu 
Lumiere" of Muttelet's Class I is indistinguishable from his ''Bleu 
Lumiere" of Class II, when using the Green Tables as a guide. Fur- 
ther, this list of Muttelet contains only 3 out of the 7 colors permitted 
in Food Inspection Decision No. 76, namely, 4 and 517 of his Class I 
and 107 of his Class II. 

An inspection of Muttelet's Class I discloses 13 Green Table 
entries, of which only 7 have been reported in the literature, as 
herein compiled and rated, in a favorable manner; of these 7, 2 were 
not on the United States market in the summer of 1907 and of the 
remaining 5, 2 are in the permitted fist of Food Inspection Decision 
No. 76; the remaining 3 are: 462. Acid Magenta (2); 512. Eosin 
(3); 520. Rose Bengal (2), and the reasons for whose noninclusion 
in the permitted list of Food Inspection Decision No. 76 have been 
given (p. 167). 

SECOND INTERNATIONAL WHITE CROSS CONGRESS. 

The Second International White Cross Congress, held in Paris, 
October 18 to 24, 1909, according to the Chemiker Zeitung, 1909, 
page 1227, adopted the following list of colors wliich were said to be 
proper for use in coloring food products. The figures in parentheses 
are the Green Table numbers; the italicized numbers are those of the 
permitted list of Food Inspection Decision No. 76. 



1. Erythrosin (516, 517), 

2. RhodaminB (504). 

3. Bordeaux S {107). 

4. Bordeaux G (170). 



5. Fast Red E (105). 

6. New Coccin (106). 

7. Ponceau 2R (55). 

8. Xylidin Scarlet (55). 



LISTS OF COLOKS RECOMMENDED BY INDIVIDUALS. 



173 



16. Lyons Blue (457). 

17. Patent Blue (440, 442). 

18. Paris Violet (451). 

19. Acid Violet (464, 465, 467, 468, 470, 

471, 472, 474, 507). 

20. Black Indulins (599). 

21. Sulphonated Nigrosin (602).' 



9. Magenta (448). 

10. Acid Magenta (462). 

11. Orange I (85). 

12. Naphthol Yellow S (4). 

13. Chrysoin (84). 

14. Auramin O (425). 

15. Acid Green (434, 435). 

It will be observed that titles 7 and 8 refer to the same Green Table 
number; this leaves, therefore, only 20 titles to consider. These refer 
to 31 different Green Table numbers which are classified as (a) only 
unfavorable reports, (6) only favorable reports, (c) conflicting reports, 
and (d) no reports, in the literature hereinbefore compiled and rated 
(see p. 63) : 

(a) 425, 434, 516, 602; total, 4. 

(6) 4, 85, 105, 107, 435, 462, 467, 517, 599; total, 9. 

(c) 55, 84, 106, 448, 451, 457, 504; total, 7. 

(d) 170, 440, 442, 464, 465, 468, 470, 471, 472, 474, 507; total, 11. 

The numbers of section (b) , of which only favorable reports are 
recorded, are the only ones here of interest; they are 9 in number, or 
less than 30 per cent of all those included in this list, and of these 9, 
5 are on the permitted Hst of Food Inspection Decision No. 76. The 
remainiag 4 are the following, the number in parentheses represent- 
ing the number of sources out of a possible 12 offering them on the 
United States market in the summer of 1907: 

105. Fast Red E (1). 

462. Acid Magenta (2). 

467. Acid Violet 6 B, not offered. 

599. Printing Blue, not offered. 

The reasons for the noninclusion of these colors in the permitted 
list of Food Inspection Decision No. 76 have been given on page 167. 

BEYTHIEN AND HEMPEL. 

Beythien and Hempel {Farher Ztg., 1909, v, 15, pp. SOI, 348, S92, 
436; abst. Ohem. Ztg., 1910, p. 58) reconamend the following colors 
for use in food products. (The numbers in parentheses are the corre- 
sponding Green Table numbers, where such connection could be 
estabHshed; the itaUcized numbers are those of the permitted list of 
Food Inspection Decision No. 76.) 



1. Alizarinblue (562, 563). 

2. Amaranth {107). 

3. Bordeaux Red (?). 

4. Brilliant Blue (?). 

5. Diamondfuchsin (448). 

6. Fast Blue (477, 599, 601, 639, 640). 

7. Fast Yellow K (9). 

8. Fast Red (63, 65, 102, 103, 105, 107, 

144). 



9. Eosin (512, 514, 515, 517, 521). 

10. Erythrosin (516, 517). 

11. Fuchsin S (462). 

12. Light Green S F yellowish {435). 

13. Indigo disulphoacid {692). 

14. Indulins (599, 601, 603). 

15. Light Blue (?). 

16. Malachite Green (427, 428). 

17. Methyl Violet (451, 454). 



174 COAL-TAR COLORS USED IN FOOD PRODUCTS. 



18. Naphthol Yellow S (4). 

19. Orange I (55). 

20. Orange L (54). 

21. Paris Violet (451). 

22. Phloxin (518, 521). 

23. Ponceau 3R (56, 57). 

24. Ponceau Red (?). 

25. Primrose (3, 513, 514). 



26. Roccellin (102). 

27. Roscellin (?). 

28. Rubin (448). 

29. Acid Yellow S (4). 

30. Acid Magenta (462). 

31. Solid Blue (?). 

32. Tropaeolin 000 (85, 86). 

33. Waterblue (480). 



For six titles (3, 4^ 15, 24, 27, and 31) no corresponding Green 
Table number could be determined. 

Of the remaining 27 titles, No. 9 includes part of No. 10, 32 includes 
19, 9 includes part of 25, 8 includes 26, 17 includes 21, 11 is identical 
with 30, and 18 is identical with 29, all on the assumption that the 
correct connections between title and Green Table numbers have been 
made. Therefore these 27 titles are, in fact, only 25 titles; of these 
25 titles, 13 refer to but one Green Table number each; the remaining 
12 titles each refer to two or more Green Table numbers. 

The Green Table numbers above given are now arranged in the 
following four classes according to the literature hereinbefore com- 
piled and rated (see p. 63) : 

(a) Only unfavorable reports: 3, 516, 639; total, 3. 

(6) Only favorable reports: 4, 65, 85, 102, 103, 105, 107, 435, 462, 477, 512, 517, 521, 
599, 692; total, 15. 

(c) Conflicting reports: 9, 86, 427, 428, 448, 451, 480, 563, 601; total, 9. 

{d) No reports: 54, 56,^ 57, 63, 144, 454, 513, 514, 515, 518, 562, 603, 640; total, 13. 

The 15 Green Table numbers of class (Jb) are the only ones here of 
interest; they include 6 out of the 7 permitted colors of Food Inspec- 
tion Decision 76; of the remaining 9, 4 (102, 477, 521, 599) were not 
on the United States market in the summer of 1907. The remaining 
5 are as follows. (The number in parentheses is the number of 
sources out of a possible 12 offering them on the United States 
market in the summer of 1907) : 

65. Fast Red B (2). 462. Acid Magenta (2). 

103. Azorubin S (6). 512. Eosin (3). 

105. Fast Red E (1). 

The reasons for the noninclusion of these colors in the permitted 
list of Food Inspection Decision No. 76 have been given on page 167. 

SUMMARY OF THREE PRECEDING RECOMMENDATIONS. 

The recommendations made by Ernst, the Wliite Cross Congi-ess, 
and Beythien and Hempel are summarized in the follomng table: 

J See page 107 for special reasons for permitting use of Ponceau 3R. 



LISTS OF COLORS RECOMMENDED BY INDIVIDUALS. 



175 



Summary of recommendations from three sources. 



Green 

Table No. 

(11). 


Unfavorable reports only. 


Number 
recom- 
mending. 


Dealers 
offering. 


Ernst. 


White 
Cross. 


Beythien 

and 
Hempel. 


3 






X 


1 

1 
1 
1 
2 
2 
1 
3 
2 
1 
1 



6 

2 
3 
1 
2 
1 


1 


94 

164 

201 

425 

434 

502 

516 

602 

639. 


I 

X 
X 
X 
X 
X 
X 












X 
X 








X 
X 


X 


X 


667 

Total.. 


X 








9 


4 


3 












Green 

Table No. 

(19). 


Favorable reports only. 


Number 
recom- 
mending. 


Dealers 
offering. 


Ernst. 


White 
Cross. 


Beythien 

and 
Hempel. 


4 

65 

85. 


X 
X 


X 


X 
X 
X 
X 
X 
X 


3 
2 
2 
2 
2 

1 
3 
3 
2 
1 
2 
3 
2 
2 
1 
1 


10 
2 
2 

6 
1 
7 
1 

4 
2 



I 




3 


X 


102 

103 

105 

107 

169 

399 

4S5 

462 

467 

477 


X 
X 
X 
X 

X 
X 
X 
X 
X 




X 
X 






X 
X 
X 


X 
X 


X 
X 
X 
X 
X 


512 

517 

521 

599 


X 
X 
X 




X 


X 


600 

692 


X 




X 


Total.. 






15 


9 


15 












Green 

Table No. 

(21). 


Conflicting reports. 


Number 
recom- 
mending. 


Dealers 
offering. 


Ernst. 


White 
Cross. 


Beythien 

and 
Hempel. 


8 

9 


X 






2 
2 
3 
3 
1 
2 
2 
1 
1 
1 


5 

1 
6 




2 
8 

2 
5 



4 
2 
3 
4 
5 

1 
5 

1 
1 




X 


13 

15 

55 

84 


X 

X 
X 








X 
X 






86 

88 

95 

106 

138 

160 

163 

197 

427 

428 

448 

451 

457 


X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 


X 








X 




















X 

X 
X 
X 




X 
X 
X 


480 

504 

563. . 


X 
X 


X 


X 


X 


584 

601 


X 






X 


Total.. 






19 


7 


9 











176 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 
Summary of recommendations from three sources — Continued. 



Green 

Table No. 

(51). 


Not reported on. 


Number 
recom- 
mending. 


Dealers 
offering. 


Ernst. 


White 
Cross. 


Beythien 

and 
Hempel. 


7 

44 

54 


X 
X 






1 

2 
2 
1 
2 
2 
2 
2 
2 
2 
2 
1 
1 
1 
1 
2 
1 
1 
2 
2 
1 
1 
1 
1 
1 
1 
1 




1 
1 




1 

2 




2 












1 




1 



1 










4 



2 














X 
X 


56 

57 

62 

63 

104 

108 

114 

133 

144 

145 

146 

147 

148 

150 

151 

157 

170 

171 

184 

198 

244 

426 

440 

442 

454 

464 

465 

468 

470 

471 

472 

474 

496 

497 

498 

505 

507 

510 

513 


X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 

X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 










X 


















X 




























X 






















X 
X 






X 


X 
X 
X 
X 
X 
X 
X 




























X 








X 
X 
X 
X 

X 


514 

515 

518 


X 
X 








50? 







583 

586 

60."^ 


X 
X 










X 
X 


640 






666 

Total.. 


X 









45 


11 


13 











These three recommendations embrace 105 different Green Table 
numbers. The following table discloses the conformity of the com- 
posite of these three recommendations to the United States market 
in the summer of 1907 : 

Number of suggested samples in the three supplementary lists found on the market, 1907. 



Data. 


Total in 

class. 


On United 

States 

market. 


Unfavorable 


11 
19 
24 
51 


7 
13 
17 
10 


Favorable 




Not reported 


Total 


105 


47 





LISTS OF COLOKS RECOMMENDED BY INDIVIDUALS. 177 

UNPUBLISHED RECOMMENDATIONS OF A MANUFACTURER. 

In addition to these published recommended lists the following 
recommendation has been made by letter by a manufacturer who 
contributed specimens of food colors to the United States market 
in the summer of 1907 : 

That for the following permitted colors of Food Inspection Decision 
No. 76, there be substituted certain colors, the Green Table numbers 
alone being here given : 



rmltted. 


Substitute 


4 


94 


56 


53 


85 


•15 


517 


521 



In regard to these proposed substitutes it is to be said that Nos. 
15 and 521 were not on the United States market in the summer of 
1907, according to the canvass made and described in Section I, 
Nos. 53 and 94 were on that market, No. 53 had not been examined 
physiologically, and No. 94 had been examined physiologically 
with only unfavorable results. The way was, therefore, not open to 
placing any of these colors on the permitted list under the procedure 
adopted. However, had No. 15 been on the market it would not 
have been placed on the permitted list, because it has been examined 
physiologically with contradictory results, while No. 521 might have 
been placed on the permitted list because it seems to have been 
examined physiologically and with only favorable results. 

BEHAL. 

As the result of careful investigation Behal {Revue Generale des 
Matieres Colorantes, 1910, p. 131) suggests the use of 21 definite 
chemical individuals which are given in the following. With the 
tabulation on page 63 as a guide these 21 colors are classified as 
unfavorable, favorable, contradictory, and not reported on. The 
itahcized figures are in the permitted list of Food Inspection Decision 
No. 76. 

UNFAVORABLE (1). 

425. Auramin (3). 

FAVORABLE (11). 



4. NaplitholYellowS(lO). 

65. Bordeaux B (2). 

85. Orange I (2). 

105. Fast Red (1). 

107. Amaranth (7). 

435. Light Green S F yellowish (4). 

97291°— Bull. 147—12 12 



462. Acid Magenta (2). 
467. Acid Violet 6B (none). 
512. Eosin (2). 
517. Erythrosin (5). 
520. Rose Bengal (2). 



178 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



CONTRADICTORY (6). 



55. Ponceau 2 R (2). 
84. Chiysoin (2). 
106. New Coccin (5). 



54. Scarlet R(l). 

64. Crystal Ponceau (1). 



427. Malachite Green (2). 
451. Methyl Violet (5). 
480. Water Blue (1). 



NOT REPORTED ON (3). 



440. Patent Blue (1). 



The ^YG in the '^ favorable'^ list which were on the United States 
market in the summer of 1907, but are not in the permitted Hst of 
Food Inspection Decision No. 76, namely: 



65. Bordeaux B (2); 
105. Fast Red (1); 
462. Acid Magenta (2); 



512. Eosin (2); 

520. Rose Bengal (2), 



are tinctorially provided for in that list; only one of the 21 colors 
recommended by Behal was not on the market of the United States 
in the summer of 1907, namely, 467 Acid Violet 6B, and this is in the 
'^favorable" list. The reasons for the non-inclusion of these colors 
are given on page 167. 

CONCLUSIONS. 

It is clear from an inspection of the preceding analysis of the six 
lists just given that the confusion referred to on page 165 as existing 
in the three recommendations made before the formulation of the 
permitted list of Food Inspection Decision 76 is not at aU diminished 
by these six lists published after the announcement of that decision, 
as is shown in the following table: 

Analysis of six lists published after the issuance of F. I. D. 76. 





Total of 

dyes 
wanted. 


Reports on physiological 
effect are — 


Physio- 
logical 
effect 
not re- 
ported. 


Number 
of dyes 
wanted 


List of- 


Unfavor- 
able. 


Favor- 
able. 


Contra- 
dictory. 


and con- 
tained in 
F. I. D. 

76. 


Emst 


88 
7 

31 

40 
4 

21 


9 


15 

I 

15 
1 


19 


45 


4 




2 


White Cross 


4 
3 
1 


7 
9 
1 
6 


11 

13 

1 

3 





Bey thien and Hempel 


fi 


Manufacturer 





Behal . . 


1 11 


5 











The same wide differences of opinion as to the four points discussed 
on ])age 166 not only continue but are accentuated. 



ANALYSIS OF PERMITTED COLORS, 1907. 179 

XIV. CHEMICAL EXAMINATIOM OF THE SEVEN PERMITTED 

COLORS, 1907. 

NEED OF CHEMICAL CONTROL. 

The most striking thing, from the chemist's point of view, in the 
literature relative to the physiological action of coal-tar colors, is 
the almost universal absence of the results of chemical examination or 
identification of the materials subjected to physiological test. There 
is hardly any description or statement of the strength or the con- 
centration of the materials examined, or of the amount or nature of 
materials not coloring matter present in the substances subjected 
to these physiological tests. It is true that some publications give 
identification tests, but few assert the identity of the material 
subjected to certain physiological tests, with the description so given. 

The need for some such chemical control as to identity and quality 
must be apparent to all having experience with the commercial 
varieties or grades of coal-tar colors. Many of these commercial 
brands of coal-tar colors contain added coloring matter other than 
the principal constituent for the purpose of correcting some defect 
unavoidably arising during the manufacture. Where those com- 
mercial brands are sold for textile and other manufacturing purposes 
there is no valid objection to such practice, because in such uses the 
tinctorial properties and effects of the commercial brands are the things 
the buyers desire and pay for, and the exact nature of the materials 
accomplishing the results is in reality of secondary importance: 
but when coal-tar colors are to be used in foods, and in addition to 
tinctorial effect the absence of any physiological action is necessary, 
it is at least of doubtful propriety to market such corrected or adjusted 
brands unless the correction or the adjustment be made with harmless 
colors. 

There are a few instances in the relevant literature where it was 
attempted to explain the different results attained by observers by 
the difference in the composition of the materials subjected to physio- 
logical test, and there are other instances showing the difficulties 
encountered in obtaining specimens of coal-tar colors which would 
always give favorable ph^^sioiogical result. 

The variation in composition of coal-tar colors may be exemplified 
by the following excerpts from the literature : 

1. Weyl ip. 91), discussing the differences between his results and 
those of Cazeneuve and Lepine with Naphthol Yellow S, states as 
follows : 

It is to be noticed, however, that Cazeneuve and Lepine state that the Naphthol 
Yellow used(Jaune NS) was difficultly soluble, so that they probably experimented 



180 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

with another substance. My own investigations were made on dogs with a preparation 
for which I am indebted to the kindness of Dr. G, Schultz, of the Aniline Manufactur- 
ing Co. of Berlin. It was purified by precipitation and recrystallization. 

2. Fraenkel (p. 578) expresses the opinion that the harmful results 
observed with Metanil Yellow (95 of the Green Tables) may be due to 
diphenylamin contained in the color, which diphenylamin may be 
a decomposition product of the Metanil Yellow, particularly since, as 
Weyl states {f. 130), it ''smelled strongly of diphenylamin." 

3. Pfeffer ( UnterscJiungen aus dem Botanischen Institut zu Tuebin- 
gen, Vol. II, p. 186) says: 

In repeating my experiments I beg that it be considered that differences in observa- 
tion may be caused by the quality of the coloring matters. For quite apart from the 
fact that the coloring matters are in part variable mixtiures of various compounds, and 
not infrequently contain foreign admixtures, the quality of the goods brought into 
market may change from time to time. Thus formerly magenta was the acetate, 
whereas to-day it is the hydrochlorid. Also foreign admixtures may be poisonous or 
may exert no influence on the absorption of color. 

4. Stilling (ArcMv, Exper. Path. Pharm.,vol. 28, 1891, p. 352) says: 

With respect to the blue pyoctanin, I have during the entire time been engaged 
in ascertaining the most effective. The things marketed by E. Merck as P. cceruleum 
have therefore now become uniform and homogeneous, which could not be the case 
at the beginning. The P. cceruleum now furnished by E. Merck is the hydrochlorid 
of pure hexamethylpararosanilin. 

The variable degrees of purity attained by products of this kind 
on the market was apparently the first cause of the prohibition by 
the German Government of the coal-tar color known as Corallin for 
use in food products— not because Corallin itself was harmful, but 
because in the manufacture of this product it was so apt to retain im- 
purities which in and of themselves produced bad effects, so that this 
particular color was specifically excluded by the German Government. 

In a few cases it is stated that the substance subjected to physio- 
logical test had been purified, but these descriptions are hardly such 
as to enable others to arrive at substantially the same result with 
reasonable certainty. 

5. Stilling m his monograph entitled Anilin Farbstoffe als Anti- 
septica (Strassburg, 1890, Pt. I, p. 16) says: 

The foregoing (relative to the action of Methyl Violet on the eyes of rabbits) holds 
only for pure substances. Many anilin colors of otherwise very antiseptic properties 
are contaminated with arsenic, particularly the otherwise useful Ethyl Violet. With 
such substance serious poisonings and death can be produced in experimental animals, 

6. Stilling in Part II of the same monograph, pages 5 and 6, says : 

Such substances (coal-tar colors) must be chemically piu-e and can not, for example, 
be any mixture of various blue or violet dyes. There is therefore a great difference 
whether a substance be tested only bacteriologically or also in addition physiologically 
and therapeutically. Two preparations may be antiseptically wholly equal, but the 
one preparation may contain harmful admixtures which produce violent irritations. 



ANALYSIS OP PERMITTED COLOES, 1907. 181 

7. Thus Weyl, spealdng of his Metanitrazotin (p. 120), describes 
the purification method as follows : 

It is dissolved in warm alcoholic solution of sodium hydroxid filtered and precipi- 
tated with hydrochloric acid. The precipitate is freed from the adhering liquid by 
the aspirator and washed with hot water. 

8. Weyl says of his Metanil Yellow {^. ISO): 

For purification the color was dissolved in water filtered and separated by the 
addition of sodium acetate. The yellow mass was freed from the adherent liquid by 
the filter pump and dissolved in hot alcohol, in which it is difficultly soluble, and 
obtained from this in the form of yellow crystals. The material used for the experi- 
ment was almost pure, as the following analytical statement shows: 0.4895 gram of 
the color dried in 105° gave 0.084 sodium sulphate. Sodium required, 6.1; found, 5.6. 
(Note. — This amounts to 91.8 per cent of theory.) 

9. Weyl {Zts. Hygiene, 1889, Vol. II, p. 34, On Safranin 
Poisoning) describes the difficulties he had in obtaining safranin on 
the market that was clean or pure; all preparations were free from 
arsenic, and contained small amounts of iron, chlorin, and traces 
of chromium. In one specimen the ash amounted to 4.8 per cent. 
The theoretical percentage of nitrogen in pure safranin is, according 
to Weyl, 15.3 per cent; in two commercial products he found 12.7 
and 12.3 per cent, respectively (83 and 80.4 per cent of theory); 
he recrystallized the specimen containing 12.7 per cent twice from 
dilute hydrochloric acid; the first recrystallization produced a speci- 
men containing 13.8 per cent (90.2 per cent of theory) of nitrogen; 
the second recrystallization produced a substance containing 14 
per cent (91.5 per cent of theory) nitrogen. 

10. Chlopin in his book {p. 110) says: 

Nevertheless, each dye was tested by me personally with the usual reagents and 
the dyeing of fabric in order to avoid the confounding of one dye with another. I 
convinced myself, from my experience, that not only druggists but the home offices 
of the makers occasionally send dyes which do not correspond to the requirements 
and resemble them only in name. 

{Page 114.) All the dyes, which according to my experiments proved to be pois- 
onous, were carefully examined for contents of arsenic, chromium, and injurious 
metals, and were found to be free from these admixtures. 

FIRST METHODS OF ANALYSIS USED. 

In the summer of 1907 there were on the United States market 30 
different specimens of the seven permitted colors of Food Inspection 
Decision No. 76. A chemical examination of those 30 specimens 
would disclose the qualitative conditions of the market so far as 
these seven permitted colors were concerned, and it was expected 
that certain limits for standards of cleanliness would be fixed by 
such an examination. 



182 COAL-TAB COLORS USED IN FOOD PRODUCTS. 

In examining these 30 specimens of the seven permitted colors 
chemically the following determinations were made: 

1. Moisture. 

2. Chlorin as chlorids. 

3. Sulphated ash, together with its iron, aluminum, calcium, and copper content, 
and the determination of the sulphuric acid in the sulphated ash. 

4. Total sulphur. 

5. Gutzeit test (test 17 of the United States Pharmacopoeia, eighth revision). 
. 6. Heavy metals test (test 121 of the United States Pharmacopoeia). 

7. Total insolubles, together with the determination of the proportion that is vola- 
tile on ignition. 

8. Ether extractive. 

The methods of analysis actually used on these 30 dye specimens 
are here given solely for the purpose of comparing them with the 
methods developed therefrom and presented beginning with page 210. 
Experience has shown that the methods here given are defective in 
many particulars, and therefore they are not to be used for exact 
work. 

MOISTURE, 

Dry a sample of each color weighing 3 grams at 105° to 108° C. for two hours. The 
loss in weight is assumed to be moisture. 

This method is not wholly accurate in the case of Naphthol Yellow, nor is it accu- 
rate in the case of Amaranth; but the scarcity of material made it seem unwise, at 
this stage, to undertake any extended investigation as to the amount or nature of the 
heating required surely to expel all moisture. The results, therefore, while not as 
accurate as might be desired, are, for the purposes of this exploratory investigation, 
sufficiently accurate for the object for which they were undertaken. 

CHLORIN AS CHLORIDS. 

Gently heat samples weighing 0.1 gram with 2 grams of sodium carbonate, and after 
destroying the greater part of the organic matter add 0.1 gram of powdered potassium 
nitrate and gently heat the whole until the organic matter is entirely destroyed. 
After cooling treat the whole with small amounts of cold water and remove from the 
crucible; effect the solution of the whole by gently heating. After cooling bring the 
bulk to about 150 cc, cool to room temperature, slightly acidify with nitric acid, pre- 
cipitate the chlorin with silver nitrate, and weigh as silver chlorid. 

SUT.PHATED ASH. 

Moisten half -gram samples with concentrated sulphuric acid, gently evaporate to 
dryness, and treat the residue with 5 cc of concentrated sulphuric acid and again 
evaporate to dryness; repeat the operation until a white ash results, when the whole 
is ignited to constant weight. After weighing take up the sulphated ash in boiling 
water (and if necessary, any undissolved material can be taken up with hydrochloric 
acid by treatment on a boiling-water bath.) Mix the two solutions and bring to a 
total volume of 200 cc. In one half thereof determine the contained sulphur by a 
precipitation with barium chlorid, and weigh as barium sulphate; in the other half 
determine iron and aluminum by precipitation with ammonia, ignite and weigh as 
ferric and aluminum oxid. No separation of any contained aluminum was under- 



ANALYSIS OF PERMITTED COLORS, 1907. 183 

taken in the filtrate from the iron; the lime was precipitated as oxalate. In the only- 
case that copper was encountered it was precipitated as eulphid before taking out the 
iron or the calcium. 

TOTAL SULPHUR. 

Mix 0.2 gram of the sample with 4 grams of sodium carbonate and 0.5 gram of potassium 
nitrate, and ignite to complete the destruction of the organic matter; take up in hot 
water; acidify with hydrochloric acid and precipitate the sulphur as barium sulphate 
with barium chlorid, • 

GUTZEIT TEST. 

Mix 2 grams of the substance with 2 grams of a mixture of 1 part of potassium nitrate 
and 5 parts of sodium carbonate and ash in a porcelain crucible over a low flame; if 
not white when cool, mix the ash with 1 gram of potassium nitrate and again ash over 
a low flame. Generally the second ashing is sufficient. Dissolve the residue in 50 
cc of hot water, boil, filter, neutralize with dilute sulphuric acid, and evaporate to 
substantial dryness on a boiling- water bath. Then add 1 cc of concentrated sulphuric 
acid and dry over a Bunsen fiame; take up the residue with 5 cc of distilled water 
containing 0.5 cc of concentrated sulphuric acid and 10 cc of a saturated solution of 
sulphurous acid; evaporate the whole to a bulk of 5 cc on a water bath; add 20 cc of 
8 per cent hydrochloric acid and subject this material to the action of 2 grams of metallic 
zinc, free from arsenic, which has been so activized by means of platinic chlorid that 
at the end of two hours more than 1 gram of zinc has dissolved and the evolution of 
gas has been constant and continuous. Condact the reaction in a flask of 60 cc capacity 
with a neck 1 cm in diameter and 6 cm long. After the introduction of the solution and 
the zinc into the flask, stopper the neck of the bottle with gauze, the lower half of 
which is dry and the upper half moistened with the test solution of lead acetate of 
the United States Pharmacopoeia. After carefully wiping the lip of the flask, cover 
it with Schleicher & Schiill quantitative filter paper which has been saturated three 
times with alcoholic mercuric chlorid solution, with complete drying between each 
saturation on one and the same spot of the filter paper. 

In the case of Naphthol Yellow S it is necessary to heat gently with 10 grams of 
sodium carbonate until the organic matter is substantially all destroyed, then add 
1.5 grams of potassium nitrate and heat to complete destruction of the organic matter. 
Dissolve the fused mass in hot water and a few drops of fifth-normal sulphuric acid; 
then make distinctly acid with the same and add an excess of 1 cc of concentrated 
sulphuric acid; evaporate first on the water bath and afterwards on asbestos until all 
odor of nitrous fumes and of hydrochloric acid has disappeared. Take up the residue 
in 5 cc of water and 15 cc of a saturated solution of sulphurous acid in water. Heat 
the whole on the water bath until no odor of sulphur dioxid remains. 

The preparation of the sample by ignition with carbonate and nitrate should not 
be done in platinum, but should be done in a porcelain crucible, since it has happened 
that as much as 0.05 mg of arsenic mixed with the dye, which had been fused in 
platinum with carbonate and nitrate, could not be detected on the mercury-chlorid 
paper, whereas 0.01 mg when similarly treated in porcelain could always be detected, 
and 0.005 mg would usually be found when done in porcelain. 

HEAVY METALS. 

Mix as much of the substance as approximately contains 1 gram of color with 10 
times its weight of carbonate of soda and ignite with the addition of 0.5 gram of potas- 
sium nitrate. Dissolve the whole in water, any undissolved material being taken up 



184 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

with hydrochloric acid, bring the two solutions together and slightly acidify with 
hydrochloric acid; dilute to 100 cc; place 10 cc in a test tube of 40 cc capacity and 
warm to 50° C. in a water bath; add 10 cc of a freshly prepared saturated solution of 
hydrogen sulphid in water, stopper the test tube well and allow the whole to stand 
in water having a temperature of 35° C. for a half hour. Dilute a 3.3 cc portion to 10 cc, 
treat as before with 10 cc of hydrogen sulphid in water for one-half hour at 35° C, and 
add to each ammonium hydrate. 

TOTAL INSOLUBLES. 

Dissolve 1 gram of the substance in 1 liter of water, filter through counterpoised 
quantitative filters, and wash with hot water until all traces of color are removed 
from the filter paper, then dry at 100° C. to constant weight and weigh; report the 
weight as total insolubles. Ignite the total insolubles in a platinum crucible and report 
the residue remaining as nonvolatile insolubles, 

ETHER EXTRACTIVE. 

Two methods were employed, the one consisting in direct extraction of the sub- 
stance in a Soxhlet apparatus by means of redistilled ether dried over sodium. 
Schleicher & Schtill extraction cartridges were used after they had been thoroughly 
extracted by ether and shown by examination that they yielded no extractive to 
ether whatever. This is a necessary precaution, because the amount of ether extrac- 
tive matter in these cartridges varies. The amount of ether extractive was determined 
by driving off the ether over a 32-candlepower incandescent lamp, finally drying and 
cooling in a desiccator. 

This method, however, is not satisfactory, since the results it gives are undoubtedly 
low and it seems that the higher the material was dried the more erratic were the 
results. Therefore the following method was used : 

Disolve 1 gram of the sample in 100 cc of water; add 0.5 gram of sodium acetate; 
extract three times with 50 cc of ether in a separatory funnel; mix the ether so recov- 
ered with 10 cc of water; separate the ether and dry with fused calcium chlorid; let 
stand from 12 to 24 hours; pour off from the calcium chlorid; distil off the ether as 
in the preceding method; acidify the color solution containing sodium acetate with 
1 cc concentrated hydrochloric acid; extract three times with 50 cc of ether, and 
proceed as before. 

RESULTS OF. CHEMICAL EXAMINATION, 1907. 

DETAILED CHEMICAL DATA ON EACH PERMITTED COLOR. 

The results of tliis examination are given in the following tabula- 
tions under the respective Green Table numbers; the serial num- 
bers refer to the numbers assigned to the specimens as they were 
received. The abbreviations ^'p." and ''n. p." opposite ''Gutzeit 
test/' and ''Heavy metals test" stand for ''pass/' and "not pass/' 
respectively, according as the specimen did or did not comply with 
those requirements; the entries opposite "Ratio," indicate the degree 
of concordance of the sulphated ash as weighed, and the contained 
SO3 calculated back to sodium sulphate and is a measure of the accu- 
racy or dependability of the sulphated ash item and its determination. 



AN-ALYSIS OF PERMITTED COLORS, 1907. 



185 



As a guide in ascertaining the conformity of these colors to their sup- 
posed standards when judged by the analytical data obtained, the 
following table may of service: 

Percentages of sulphur, sodium, and sulphated ash properly belonging to each of the seven 

permitted colors. 



Green 
Table 
No. 



4 

56 

85 

107 

435 

517 



Name of colors. 



Naphthol Yellow 

Ponceau 3 R 

Orange I 

Amaranth 

Light Green 

Erythrosin 

Indigotin 



Sulphur. 



8.95 
12.97 

9.16 
15.92 
]1.12 

(') 
13.75 



Sodium. 



12.87 
9.33 
6.58 

11.44 
8.31 
5.24 
9.89 



Sul- 
phated 
ash. 



39.73 
28.80 
20.31 
35.32 
25.64 
16.17 
.30.52 



1 lodin in No. 517=57.7 per C8nt. 
Detailed analytical data obtained on several samples of each of the permitted colors (per cent), 

GREEN TABLE NO. 4. NAPHTHOL YELLOW S. 



Determinations. 


Serial Nos. 


23. 


73. 


108. 


142. 


187. 


Moisture 


0.70 
6.73 
2.65 

.07 

.04 

38.00 

38.18 

100.3 

12.32 

8.72 

n.p. 

"& 

.03 
.02 
.34 
.98 
L32 
.062 


0.28 
3.47 
1.37 

.07 

None. 

48.8 

49.57 

101.6 

15.82 

9.47 

n.p. 

n.p. 

None. 

None. 

None. 

.15 

.90 

L05 

.042 


0.28 

LC2 

.40 

.07 

None. 

47.1 

47.32 

100.5 

15.46 

12.63 

n.p. 

n.p. 

None. 

None. 

None. 

.14 

.70 

.84 

.04 


0.60 
.61 
.24 

.07 

None. 

51.4 

5L76 

100.7 

16.66 

12.42 

n.p. 

n.p. 

None. 

None. 

None. 

.16 

.75 

.91 

.03 


0.33 


NaCl 


2.86 


Na as NaCl 


1.13 


Sulphated ash: 

Al and Fe 


.28 


Ca . . 


None. 


Na2S04 


49.2 


SOsin Na2S04— NajSOi 


49.44 


Ratio 


100.5 


Na as Na2So4 


15.95 


Total sulphur 


12.32 




n.p. 


Hea\^ metals test 


n.p. 




.05 


Nonvolatile 


None. 


Volatile 


.05 




.10 




.32 




.42 


Ether extract solid 


.022 







Determinations. 


Serial Nos. 


201, 


209. 


228. 


272. 


280. 




0.50 
23.67 
9.31 

.21 
.03 
49.20 
49.75 
101.1 
15.95 
6.35 
n.p. 

.20 
.10 
.14 
.33 
.47 
.10 


0.60 
4.08 
1.61 

None. 

None. 
53.10 
53.76 

101.3 
17.22 
12.56 
n.p. 

None. 

80 

.25 

1.08 

1.33 

.004 


0.32 
2.86 
L13 

.07 

None. 

55. 60 

56.45 

101.5 

18.03 

13.42 

n.p. 

.10 
.02 
.08 
.90 
.98 
.13 


2.12 
3.26 
L28 

.07 

None. 

45.60 

45.80 

100.4 

14.79 

10.50 

P- 

".16 

None. 
.90 
.15 
.72 
.87 
.04 


9.07 


NaCl 


9.39 


Na as NaCl 


3.70 


Sulphated ash: 

Al and Fe 


.07 


Ca 


.07 


Na2S04 


40.20 


S03inNa2S04=Na2S04 


40.14 


Ratio '. 


99.84 


Na as Na2S04 . . 


13.03 




7.55 


Gutzeit test 


p. 




n.p. 


Total insolubles 


L30 


Nonvolatile 


.04 


Volatile 


1.16 


Acetate ether extract 


.10 


Acid ether extract 

Total ether extract 


.77 
.87 


Ether extract solid 


.02 







186 



COAL-TAB COLORS USED IN FOOD PRODUCTS. 



Detailed analytical data obtained on several samples of each of the permitted colors {per 

cent) — Continued. 



GREEN TABLE NO. 56. PONCEAU 3R. 



Determinations. 


Serial 
No. 9. 


Determinations. 


Serial 
No. 9. 


Moisture 


5.76 

19.89 

7.84 

.28 
None. 
38.10 
38.56 


Ratio 


101.20 


NaCl 


Na as Na2S04 . 


12 36 


Na as NaCl 


Gutzeit test 


P- 
n. p. 


Sulphated ash: 


Heavy metals test 


Al and Fe 




.28 


Ca 


Acid ether extract 


.83 


Na2S04 




1.11 


SO3 in Na2S04= Na2S04 


Ether extract solid . . 


.326 









GREEN TABLE No. 85. ORANGE I. 



Determinations. 


Serial Nos. 


Determinations. 


Serial Nos. 


16. 


224. 


16. 


224. 


Moisture 


11.06 
8.78 
3.18 

.14 

None. 
30.80 
31.18 

101.3 
9.99 


5.39 
3.51 
L38 

.07 
.14 

18.00 

18.09 

100. 50 

5.84 


Total sulphur 


10.12 
P- 

ii6 

.20 
1.30 
.02 
.20 
.22 
.214 


8.34 


NaCl 


Gutzeit test 


n.p. 


Na as NaCl 


Heavy metals test 


Sulphate ash: 

Aland Fe 


Total insolubles 


Nonvolatile 


.20 


Ca 


Volatile 

Acetate ether extract 


.35 


Na2S04 


.62 


SO3 in Na2S04— Na2S04 




.20 


Ratio 


Total ether extract 


.82 


Na as Na2S04 


Ether extract solid 


.254 









GREEN TABLE No. 435. LIGHT GREEN SF YELLOWISH. 



Determinations. 



Serial Nos. 



92. 



168. 



233. 



Moisture 

NaCl 

NaasNaCl 

Sulphate ash: 

Aland Fe 

Ca 

Na2S04 

S0.3inNa2S04=Na2S04 

Ratio 

NaasNa2S04 

Total sulphur 

Gutzeit test 

Heavy metals test 

Total insolubles 

Nonvolatile 

Volatile 

Acetate ether extract 

Acid ether extract 

Total ether extract 

Ether extract solid 



8.32 
.041 
.016 

.70 

3.29 

9.00 

7.78 

86.46 

2.92 

11.48 

Tr.(p.) 

P- 

.20 

None. 

.20 

.02 

.05 

.07 

.026 



5.08 
.102 
.040 

.28 

.00 

43.40 

43.96 

101. 30 

14.07 

15.44 

Tr. (p.) 

aI 

.06 
.39 
.02 
.05 
.07 
None. 



5.04 

1.735 

.683 

.14 

.085 

48.00 

46.68 

95.92 

15.56 

15.82 

Heavy. 

P- 

.75 

.60 

.15 

.05 

.05 

.10 

.02 



4.15 
1.530 
.603 

.14 

.085 

63.00 

53.62 

101.3 

17.19 

16.75 

Heavy. 

P- 

.95 

.60 

.35 

None. 

.05 

.05 

.02 



GREEN TABLE No. 107. AMARANTH. 



Determinations. 


Serial Nos. 


82. 


96. 


130. 


162. 


177. 


219. 




4.24 
38. 91 
15.32 

.14 

.215 

65.20 

66.50 


6.46 
12.79 
5.04 

.07 
.857 
53. 20 
55.60 


6.23 
35.79 
14.10 

.14 

.93 

59.80 

60.30 


9.81 
25.39 
10.00 

.42 

.428 
48.80 
49. S2 


4.20 
28.45 
11.21 

.42 
.428 
60.00 
61.26 


8.24 


NaCl 


24 21 


Na as NaCl 


9 54 


Sulphate ash: 

Al and Fe 


.21 


Ca 


.57 


Na2S04 


49.80 


SO!.inNa2S04=Na2S04 


50.72 



ANALYSIS OF PERMITTED COLORS, 1907. 



187 



Detailed analytical data obtained on several samples of each of the permitted colors (per 

cent) — Continued. 

GREEN TABLE No. 107. AMARANTH— Continued. 



Determinations. 


Serial Nos. 


82. 


96, 


130. 


162. 


177. 


219. 


Ratio 


102.00 

21.13 

8.62 

None. 

n.p. 

.12 
.18 
.08 
.07 
.15 
.024 


100. 80 
17.22 
13.02 
None, 
n.p. 

1.10 
.40 
.15 
.15 
.30 
.062 


100. 80 

19.39 

8.57 

None. 

n.p. 

n.p. 

2.05 

1.10 

.95 

.18 

.15 

.33 

.052 


101.5 
15.82 

9.42 
.09 
n.p. 
n.p. 

1.05 
.35 
.70 
.20 
.03 
.23 
.040 


102.1 

19.45 

11.09 

None. 

n.p. 

.35 
.55 
.02 
.03 
.05 
.044 


101.9 


Na as Na2S04 


16.14 


Total suipJiur 


8.54 


Copper 


None. 


Gutzeit test 


n.p. 


Heavy metals test 


n.p. 

2.40 


Total insolubles 


Nonvolatile 

Volatile 


1.15 
1.25 




.30 


Acid ether extract 


.10 


Total ether contract 


.40 




.054 







GREEN TABLE NO. 517. ERYTHROSTN. 



Determinations. 


Serial Nos. 


184. 


200. 


216. 


254. 


J.roistnre 






9.6 












Sulphated a<'h: 

Al and Fe 


0.14 
None. 
39.00 
39.44 
12.65 
P- 

.i- 

.04 
.56 
.80 


0.14 
None. 
35. 69 
35.44 
11.52 
n.p. 

io 

None. 
.20 
.35 


.14 

None. 

31.80 

32.46 

10.40 

p. 

is 

.20 
.45 
.10 


0.28 


Ca . 


No re 


Na2S0H 


26.4 


SO3 in Na2S04=Na2S04 

Na as Na2S04 


26.8 
8.56 


Gutzeit test 


P- 


Heavy metals test . . . 


Total insolubles 


Nonvolatile 


.20 


Volatile 


.70 


Acetate ether extract . . 


.10 


Total ether extract 




Ether extract solid 


.024 


.07 


.02 


.02 







GREEN TABLE NO. 692. INDIGO DISULPHO ACID. 



Detenninations. 


Serial Nos. 


Determinations. 


Serial Nos. 


90. 


195. 


249. 


90. 


195. 


249. 


Moisture 


7.25 
7.02 
2.77 

.42 

.57 

26.20 

26.74 

102. 10 

8.50 


5.32 
28.66 
11.29 

.28 

.14 

55.40 

56.64 

102.20 

17.97 


7.31 
7.02 
2.77 

.56 

.71 

26.60 

27.36 
102.8 
8.03 


Total sulphur 


10. 30 

?(?) 
1.55 
.55 
L05 
.02 
.05 
.07 
.002 


10.30 

^.§ 

None. 
.80 
.02 
.10 
.12 
.014 


10.09 


NaOl. 


Guczeit test 


1.15 


NaasNaCl 


Heavy metals test 

Total insolubles 


Sulphated ash: 

AlandFe 




.50 


Ca 


Volatile 


.65 


Na2S04 .. 


Acetate ether extract 

Acid ether extract 

Total ether extract 

Ether extract solid 


.02 


RO3 in Na2S04=Na2 
SOj 


.03 

.05 


Ratio 


.02 


NaasNajSOi 









RECALCULATION OF ANALYTICAL DATA ON BASIS OF COLORING 
MATTER PRESENT. 

The difficulties in the way of translating these analytical data into 
proximate constituents are so great, in so many of the cases, as to 
make any attempts to obtain practical results in that way absolutely 



188 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



useless; the amount of material on hand was unfortunately so small 
at the beginning (2 ounces or less, in most instances) that the utmost 
economy of material was necessary to get the data reported, on 
account of the large amount of material needed in the exploratory 
work done in trying out the methods for determining arsenic, heavy 
metals, and ether extractives. 

In the arsenic test the coloring matter, as a whole, was considered, 
and no attempt was made to get at the actual amount of real coloring 
matter in the exact weights of the material as a whole, used for such 
examination, and consequently the results are not translatable into 
actual weights of real color used. It is obvious that if 2 grams, or 
other weight of the substance as a whole, failed to pass any test when 
the whole amount was considered as though it were all color, the 
material could not possibly have passed those tests if amounts thereof, 
corresponding to the prescribed weights of actual color used, were 
taken; also it is clear that if the sample, as a whole, passed a given 
test, at a given weight thereof, it would not necessarily have passed 
that test had an amount thereof, corresponding to that same weight 
of actual color, been used. 

The amount of actual or real coloring matter in 27 of these 30 
specimens is not greater than shown in the following: 

Per cent of actual coloring matter in 27 samples. 



Name of color. 



Serial 
No. 



Percent. 



Serial 
No. 



Per cent. 



Naphthol Yellow S 

Ponceau 3R 

Orange I 

Amaranth 

Light Green SF Yellowish 

Erythrosin 

Indigo Disulpho Acid 



23 

73 

108 

142 

187 

9 

16 

82 

96 

130 

57 

92 

216 

90 

195 



91.20 
95.20 
97.86 
97.88 
96.34 
73.24 
78.44 
56.40 
78.95 
55.60 
91.37 
94.30 
89.65 
84.11 
65.10 



201 
209 
228 
272 
280 



75.56 
93.19 
95.72 
92.81 
79.47 



224 


89.76 


162 


63.52 


177 


66.40 


219 


64.25 


168 


92.37 


233 


93.32 


249 


84.47 



In order to make these analytical results comparable among them- 
selves and with other analytical results later to be given, the items 
common salt, volatile and nonvolatile insolubles, total insolubles, 
acetate ether extract, acid ether extract, and total ether extract of 
the preceding tabulations have been recalculated in parts per 100 
of actual or real coloring matter as just enumerated: 



ANALYSIS OF PERMITTED COLORS, 1907. 



189 



Analytical data recalculated to parts per hundred of coloring matter present. 

GREEN TABLE NO. 4. NAPHTHOL YELLOW S. 



Determinations. 










Serial 


Nos. 










23. 


73. 


108. 


142. 


187. 


201. 


209. 


228. 


272. 


280. 


Common salt 


7.38 


3.64 


1.04 


0.62 


2.97 


31.53 


4.38 


2.99 


3.51 


11.82 






Insolubles: 

Volatile 


.02 
.03 


.00 
.00 


.00 
.00 


.00 
.00 


.05 
.00 


.13 

.27 


.86 
.00 


.02 
.10 


.97 
.00 


1 46 




.05 






Total 


.05 


.00 


.00 


.00 


.05 


.40 


.86 


.12 


.97 


1.51 






Ether extract: 

Acetate 


.37 
1.07 


.16 
.95 


.14 

.72 


.16 

.77 


.10 
.33 


.19 

.44 


.27 
1.16 


.08 
.94 


.16 

.78 


.13 


Acid 


.97 






Total 


1.44 


1.11 


.86 


.93 


.43 


.63 


1.43 


1.02 


.94 


1.10 







GREEN TABLE NO. 56. PONCEAU 3R. 



Determinations. 


Serial No. 
9. 


Determinations. 


Serial No. 
9. 




27.16 


Ether extract: 

Acetate 




Insolubles: 


0.38 


Volatile 


Acid 


1 13 


T>J nn vnl ati 1 p. 




Total 








1.51 









GREEN TABLE NO. 85. ORANGE I. 



Determinations. 


Serial Nos. 


Determinations. 


Serial Nos. 


16. 


224. 


16. 


224. 


Common salt 


11.19 


3.91 


Ether extract: 


0.02 
.25 






0.69 
.23 




L66 
.25 


.39 
.23 


Acid 


VolaUlp 


Total 






.27 


.92 








Total 


1.91 


.62 









GREEN TABLE NO. 107. AMARANTH. 



Determinations. 


Serial Nos. 


82. 


96. 


130. 


162. 


177. 


219. 




68.89 


16.20 


64.37 


39.97 


42.85 


37.39 






Insolubles: 

Volatile 


.32 
.21 


.51 
1.39 


1.71 

1.98 


1.10 
.55 


.83 
.54 


1.93 


Nonvolatile 


1.78 






Total 


.53 


1.90 


3.69 


1.65 


1.37 


3 71 






Ether extract: 


.14 
.12 


.19 
.19 


.32 
.27 


.31 

.05 


.03 
.05 


.46 


Acid 


.15 






Total 


.26 


.38 


.59 


.36 


.08 


.61 







190 



COAL-TAR COLORS USED IN FOOD PRODUCTS. 



Analytical data recalculated to parts per hundred of coloring matter present — Continued. 

GREEN TABLE NO. 435. LIGHT GREEN SF YELLOWISH. 



Determinations. 


Serial Nos. 


57. 


92. 


168. 


232. 


Common salt 


0.04 


0.10 


1.88 


1 64 






Insoluble: 

Volatile 


.22 
.00 


.41 
.06 


.16 
.65 


.38 


Nonvolatile 


.64 






Total 


.22 


.47 .81 


1.02 






Ether extract: 

Acetate 


.02 
.05 


.02 
.05 


.05 
.05 


.05 


Acid .. . 


05 






Total 


.07 


.07 


.10 


.10 







GREEN TABLE NO. 517. ERYTHROSIN. 



Determinations. 


Serial 
No. 216. 


Determinations. 


Serial 
No. 216. 


Common salt 




Ether extract: 
Acetate 








U 


Insoluble: 


0.50 
.22 






Volatile 


Total 






.11 








Total 


.72 









GREEN TABLE NO. 692. INDIGO SULPHO ACID. 



Determinations. 


Serial Nos. 


Determinations. 


Serial Nos. 


90. 


195. 


249. 


90. 


195. 


249. 




8.35 


44.02 


8.31 


Ether extract: 


0.02 
.06 


0.03 
.15 






02 




L25 

.59 


1.23 
.00 


.77 
.59 


Acid 


.04 


Volatile 


Total 






.08 


.18 


.06 








Total 


1.84 


1.23 


1.36 









MARKET QUALITY OF THE SEVEN PERMITTED COLORS. 

That the quahty of the lots of the seven permitted colors of Food 
Inspection Decision No. 76 offered on the markets of the world after 
the issuance of that decision was no better than that of the lots just 
reported, if as good, appears from the paper of E. G. Kohnstamm enti- 
tled, ''Certified Food Colors: The Difficulties in the Way of then- 
Manufacture,'' presented to the Seventh International Congress of 
Applied Chemistry held in London, May and June, 1909, and pub- 
lished in abstract form. This abstract reads as follows: 

The coal-tar colors permitted under the food and drugs act of the United States are 
seven in number, which must be in a high state of purity. The author states that none 
of the colors on the markets of the world, at the time of testing, would meet these 
requirements. 



1907. 191 

Of these seven colors, 189 samples, from every possible source, and representing all 
the leading manufacturers, are here reported on, and the results of their examina- 
tion reasonably estabhsh the necessity of food color certification. Of these 189 sam- 
ples, the worst were offered for food coloring purposes and seemed to be so offered 
because unfit for any other purpose. 

Naphthol Yellow S. — Sixty-four samples examined, ranging in shade from clear 
bright yellow to a dirty brownish or green color. All contained Martins Yellow, some 
more than 1 per cent thereof; some contained as high as 2 per cent and even 3 per cent 
unconverted initial material or decomposition products. Forty-one contained exces- 
sive arsenic and 29 excessive heavy metals. 

Orange I. — Twenty-eight samples examined; all contained decomposition products 
varying fi'om a slight amount to over 50 per cent; free or-naphthol was found in most 
samples; in 12 it was as high as 2 per cent; insoluble matters were as high as 1 per cent; 
lead to the extent of 0.5 per cent was found in one sample; shading by r.dded colors 
and excessive amounts of arsenic; lead and iron were frequent. 

Amaranth. — Thirty-eight samples examined; none were pure, and all contained 
arsenic in excessive amounts, and in one case as high as 0.1 per cent; all contained 
added color, principally an acid-violet. Iron as high as 0.1 per cent; insoluble matter 
as high as 1^ per cent; was most heavily loaded with salt of all seven colors. 

Ponceau 3R. — Thhty-six samples examined; the purest of all colors tested; not 
toned; heavily loaded with salt; much insoluble matter was present; decomposition 
products were absent; iron, 0.01 per cent; 12 contained excessive amounts of arsenic 
and 14 contained excessive amounts of heavy metals, 

Erythrosin. — ^Twelve samples examined; 10 were not erythrosin at all; of the other 
two, one was low in iodin and one contained arsenic. 

Light Green 8 F Yellowish. — Thirteen samples examined; only one free from 
arsenic; nine contained lead or copper; one contained manganese; none were loaded. 

Indigo Disulphonic Acid. — Eight samples examined; none were pure; the iron con- 
tent was as high as 1.5 per cent; all were loaded with salt or Glauber's salt. One con- 
tained excessive amount of arsenic and two excessive amounts of heavy metals. 

The difficulties consist in keeping the undesirable materials out of the dyes or in 
separating them from the crude dyes, or both. 

In this connection the following statement made by Dr. E. Ludwig^ 
of Vienna, at the International Congress of Medicine held in Buda- 
pest, August, 1909, may be of interest: 

The author, at an order of a comt, at the beginning of the seventies in the last cen- 
tury, examined approximately 200 samples of food products confiscated as suspicious 
and taken from numerous sales places of a then suburb of Vienna; these samples 
included solid confectionery, fruit sirups, spirits, etc. He found that more than 
90 per cent of these things were colored with magenta and contained arsenic. In some 
of the sales places the preparation used for coloring, the so-called " couleur, " was 
found, which proved to be a solution of magenta and in which there were contained 8 
per cent of arsenic in the form of arsenous acid and of arsenic acid. According to the 
statements of a qualified dyestuff maker, this ''couleur" was a mother liquor from 
magenta manufacture, which was very difficultly saleable and which, however, a 
conscienceless agent had talked onto ignorant producers of and dealers in foods. 

Schacherl {p. 10^6) says: ''It should be required of all permitted 
coloring matters that they shall not contain substances which are 
harmful to health, or even suspicious, either in chemical union or as 
contaminations.'' The following pages (Section XV) show how 
closely this requirement has been met as a result of quality control 
on the part of the Department of Agriculture. 



192 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

XV. GUIDES IN DETERMINING DEGREE OF PURITY AND 

CLEANLINESS. 

In view of the absence of any statements in the Hterature defining 
the purity of the colors physiologically examined with such accuracy 
that another could obtain with reasonable certainty the same degree 
of cleanliness, it became necessary to devise some guide, no matter 
how empirical, in the setting up of standards, tentative or otherwise. 

As a first consideration it was held that, in view of the fact that all 
of the physiological work had been done with specimens of coal-tar 
colors of commercial purity, it would be reasonable to suppose that 
coal-tar colors produced in the purest form possible with present-day 
methods would certainly be as clean and as free from admixture as 
any of the commercial products subjected to physiological test. It 
was considered unreasonable to expect that increasing the degree of 
purity of these substances could in any way increase any harmful 
property possessed by them. Certainly in the case of Naphthol 
Yellows, where Martins Yellow is a usual contaminant, it can hardly 
be maintained that decreasing the amount of Martins Yellow would 
increase any harmful property which might reside in Naphthol Yel- 
low S proper; in the case of Ponceau 3 E, it could hardly be argued 
that any undisazotized base or decomposition products of diazo 
compounds tended to correct or counteract any harmful property 
that might reside in Ponceau 3 E, proper; nor could it be maintained 
that Orange I free from uncombined alpha-naphthol was more harmful 
than Orange I, contaminated with alpha-naphthol, and so on through 
the list of the seven permitted colors. This point would not be 
raised had it not been pressed repeatedly by different persons as a 
serious objection to quality control and purity standards of the seven 
permitted colors of Food Inspection Decision No. 76. 

With this rule in mind, and referring to the tabulated results of the 
analyses of the 30 specimens of the seven permitted colors just given, 
the items in the analytical statements will each be separately 
discussed. 

Common salt and ether extractive. — Common salt is a legitimate com- 
ponent of commercial brands of coal-tar colors in so far as these 
coal-tar colors are obtained by the so-called '' salting out" process. 
The coal-tar colors are recovered from solution by the addition of 
common salt, which has the peculiar property of separating the coal- 
tar color from the water solution as an undissolved solid. The 
coal-tar color so obtained will contain more or less salt, which, from a 
commercial manufacturing point of view, is therefore an unavoidable 
constituent. The amount of salt so accompanying the coal-tar 
color depends upon the amount added to the color solution, and this 
is greatest when complete exhaustion of the coal-tar color solution 
is attempted. It is a matter of common experience that, as a rule, 



GUIDES IN DETERMINING PURITY. 193 

the coal-tar color first separating in the salting-out process is cleaner 
and less contaminated than the portions last separating. In an 
endeavor to recover as far as possible all the dissolved coal-tar 
coloring matter the manufacturer adds a large excess of salt, and 
this carries with it a large amount of organic matter not coloring 
matter, as can be seen from the preceding analyses, where a high 
salt content is almost always accompanied by a high ether extract 
content. The ether extract content is a measure of the dirt or 
organic impurities of the coloring matter. 

The objection to an excessive amount of salt in coal-tar coloring 
matters, when they are to be used for food-coloring purposes, does 
not reside in the salt per se, but is due to the fact that a high salt 
content seems generally to be accompanied by an unnecessarily 
large amount of organic material not coloring matter, and nothing 
good is known of such material, which is more than likely to be 
harmful. 

The acetate ether extract is supposed to represent that part of the 
organic material not coloring matter which has no, or only slightly, 
basic properties; the acid ether extract is supposed to represent that 
part of the organic material not coloring matter which has acid 
properties. In the case of Naphthol Yellow S the acid ether extract 
will contain all of the Martins Yellow, and very likely will consist 
substantially of it. In the case of Erythrosin, of course, no acid ether 
extraction was attempted because the color acid is itself ether- 
soluble. 

The following tabulation shows the percentages of salt based on 
the amount of coloring matter present contained in 26 of the specimens 
before reported on, arranged under each of the seven permitted 
colors : 

Naphthol Yellow S: 0.62; 1.04; 2.97; 2.99; 3.51; 3.64; 4.38; 7.38; 11.82; 31.53. 
(Average, 6.99.) 
Ponceau 3 R: 27.16. 
Orange I: 3.91; 11.19. (Average, 7.55.) 

Amaranth: 16.20; 37.39; 39.97; 42.85; 64.37; 68.89. (Average, 44.95.) 
Light Green SF Yellowish: 0.04; 0.10; 1.64; 1.88. (Average, 0.92.) 
Indigo Disulpho Acid' 8.31; 8.35; 44.02. (Average, 20.23.) 

The following figures give the same data for the acetate, acid, and 
total, ether extract : 

Ether extractives, 

ACETATE ETHER EXTRACT. 

Naphthol Yellow S: 0.08; 0.10; 0.13; 0.14; 0.16; 0.16; 0.16; 0.19; 0.27; 0.37. (Aver- 
age, 0.18.) 

Ponceau 3 R: 0.38. 

Orange I: 0.02; 0.69. (Average, 0.36.) 

Amaranth: 0.03; 0.14; 0.19; 0.31; 0.32; 0.46. (Average, 0.24.> 

97291°— Bull. 147—12 13 



194 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Light Green SF Yellowish: 0.02; 0.02; 0.05; 0.05. (Average, 0.035.) 

Erythrosine: 0.11. 

Indigo Disulpho Acid: 0.02; 0.02; 0.03. (Average, 0.03.) 

ACID ETHER EXTRACT. 

Naphthol Yellow S: 0.33; 0.44; 0.72; 0.77; 0.78; 0.94; 0.95; 0.97; 1.07; 1.16. (Aver- 
age, 0.81.) 

Ponceau 3 R: 1.13. 

Orange I: 0.23; 0.25. (Average, 0.24.) 

Amaranth: 0.05; 0.05; 0.12; 0.15; 0.19; 0.27. (Average, 0.14.) 

Light Green SF Yellowish: 0.05; 0.05; 0.05; 0.05. (Average. 0.05.) 

Indigo Disulpho Acid: 0.04; 0.06; 0.15. (Average, 0.08.) 

TOTAL ETHER EXTRACT. 

Naphthol Yellow S: 0.43; 0.63; 0.86; 0.93; 0.94; 1.02; 1.10; 1.11; 1.43; 144. (Aver- 
age, 0.99.) 

Ponceau 3R: 1.51. 

Orange I: 0.27; 0.92. (Average, 0.59.) 

Amaranth: 0.08; 0.26; 0.36; 0.38; 0.59; 0.61. (Average, 0.38.) 

Light Green SF Yellowish: 0.07; 0.07; 0.10; 0.10. (Average, 0.09.) 

Erythrosin: 0.11. 

Indigo Disulpho Acid: 0.06; 0.08; 0.18. (Average, 0.11.) 

Insoluble matter. — The amount of insoluble matter (total, volatile, 
and nonvolatile) is a measure of the cleanliness of the materials 
used, as well as of the cleanliness of treatment during the manu- 
facture of the coloring matter. The following tabulation shows the 
variations in these three figures for each of the 26 specimens of the 
7 permitted colors, examined, as in the preceding cases : 

Insoluble matter. 

VOLATILE INSOLUBLE. 

Naphthol Yellow S: 0.00; 0.00; 0.00; 0.02; 0.02; 0.05; 0.13; 0.86; 0.97; 1.46. (Aver- 
age, 0.35.) 

Orange I: 0.39; 1.66. (Average, 1.03.) 

Amaranth: 0.32; 0.51; 0.83; 1.10; 1.71; 1.93. (Average, 1.07.) 

Light Green SF Yellowish: 0.16; 0.38; 0.22; 0.41. (Average, 0.29.) 

Erythrosin: 0.50. 

Indigo Disulpho Acid: 0.77; 1.23; 1.25. (Average, 1.08.) 

NONVOLATILE INSOLUBLE. 

Naphthol Yellow S: 0.00; 0.00; 0.00; 0.00; 0.00; 0.00; 0.03; 0.05; 0.10; 0.27. (Aver- 
age, 0.05.) 

Orange I: 0.23; 0.25. (Average, 0.24.) 

Amaranth: 0.21; 0.54; 0.55; 1.39; 1.78; 1.98; (Average, 1.08.) 

Light Green SF Yellowish: 0.00; 0.06; 0.64; 0.65. (Average, 0.34.) 

Erythrosin: 0.22. 

Indigo Disulpho Acid: 0.00; 0.59; 0.59. (Average, 0.36.) 

TOTAL INSOLUBLE. 

Naphthol Yellow S: 0.00; 0.00; 0.00; 0.05; 0.05; 0.12; 0.40; 0.86; 0.97; 1.51. (Aver- 
age, 0.40.) 

Orange I: 0.62; 1.91. (Average, 1.27.) 



GUIDES IN DETERMINING PURITY. 195 

Amaranth: 0.53; 1.37; 1.65; 1.90; 3.69; 3.71. (Average, 2.14.) 
Light Green SF Yellowish: 0.22; 0.47; 0.81; 1.02. (Average, 0.63.) 
Erythrosin: 0.72. 
Indigo Disiilpho Acid: 1.23; 1.36; 1.84. (Average, 1. 48.) 

Work subsequent to these analyses showed that the insoluble 
matter, particularly the nonvolatile insoluble matter, was greater 
in certain batches than in others, and that these amounts were in 
excess of the maximum amounts reported therefor. Examination 
showed that these increased amounts of insoluble matter were 
probably due to variations in the water delivered to the factories 
by their respective municipal water supplies, since it was noted that 
in two or more cases the batches containing an exceptionally large 
amount of nonvolatile insoluble matter were manufactured at a 
time when the city water supply was abnormally hard; this item, 
therefore, has been made in some instances a little more elastic than 
the preceding analyses would seem to justif}^. 

Arsenic. — Examination of the preceding tabulations shows that 
14 out of 30 specimens tested passed the Gutzeit test for arsenic, and 
16 failed to pass. 

Heavy metals. — Inspection of the preceding tables shows that 13 
out of 30 specimens passed this test, and that 17 failed to pass. 

Combined arsenic and heavy metals test. — Inspection of the preceding 
tables shows that 11 out of 30 passed both tests jointly; that 3 
passed the arsenic test and failed to pass the heavy metals test; and 
that 2 passed the heavy metals test and failed to pass the arsenic 
test. 

Moisture. — The amount of moisture, as inspection of the preceding 
analyses shows, is variable, and is a factor not under easy control. 
As long as the coloring matters, submitted for foundation certification 
were in powder form and the analyses disclosed the actual percentage 
of coloring matter it was considered that any control of this item 
would involve an amount of labor and provide opportunities for 
friction wholly out of proportion to any benefit that at present could 
be reahzed therefrom. Therefore such control was not instituted, 
although it by no means follows that the time may not come when 
control of this item will be necessary. 

SulpJiur and sulpJiated asJi. — These two determinations in the 
case of all the permitted colors, except Erythrosin, give a rough 
measure of the extent of the sulphonation and of the saturation of 
the sulphonic acids with sodium. It is not the function of these 
two items to exclude the isomeric modifications, nor was any test 
applied to such of these 30 specimens as were examined in this respect 
to determine the presence or absence of such products. The attempts 
made in this direction are of a later date than the analyses already 
reported, and are indicated on page 210 of this report. 



196 COAL-TAE COLORS USED IN FOOD PRODUCTS. 

With these data available, and with the general rule stated at the 
opening of this section in mind, it was regarded as the proper course, 
when determining upon standards, to require that each color should 
pass the combined heavy metals and arsenic test of the United States 
Pharmacopoeia, and in other respects should be as clean and as high- 
grade as the best of each class given in the preceding analyses. Just 
how closely it was possible to adhere to this rule will be shown 
later. 

With respect to the arsenic requirement, there has been a great 
deal of discussion brought on by those interested in the manufacture 
of these colors. It was protested that colors could not be made 
uniformly and continuously under manufacturing conditions, which 
would contain an amount of arsenic so small that a quantity of the 
product containing 2 grams of the coloring matter in question would 
not respond to the Gutzeit test in the United States Pharmacopoeia. 
The results above given with respect to conformity or nonconformity 
to the Gutzeit test, were, with a great deal of justification, not regarded 
as conclusive, because, as has been previously stated, there was no 
certainty that the amount of coloring matter actually taken did 
represent 2 grams. In view of the fact that the United States Phar- 
macopoeia prescribes for the only coal-tar color in it, namely, Methy- 
lene Blue, that it shall be so free from arsenic that 2 grams fail to 
respond to the Gutzeit test, it was considered perfectly justifiable 
to adhere to that requirement until it could be conclusively shown 
that it was unreasonable and incapable of attainment. Results 
described in the pages that follow show that it has been possible to 
make all the 7 permitted colors of Food Inspection Decision No. 76 
so free from arsenic that they comply with the Pharmacopoeia! 
test. 

With respect to the heavy metals, no deviation was necessary for 
the nonferrous metals from the test of the Pharmacopoeia; for iron, 
however, it was found necessar}^ to increase the limit to substantially 
0.005 part per 100 of actual coloring matter. The reason for this is 
that at one time or another all of the seven permitted coloring matters 
in the course of their manufacture come in contact Avith, or are con- 
tained in, vessels of iron, and it seems to be almost impossible to 
keep iron out to an extent which would bring the color within the 
pharmacopoeial test. It has been shown that there were 13 colors 
on the market in 1 907 which contained so little iron that they failed 
to respond to the heavy metals test of the Pharmacopoeia in that 
respect; but here again the same criticism holds good as in the arsenic 
test, that there is no certainty that the amounts taken for the heavy 
metals tests were equivalent in each case to 1 gram of actual coloring 
matter, and subsequent experience seems to confirm the correctness 



GUIDES IJT DETEEMININ"G PURITY. 197 

of that criticism; therefore the rule for cleanhness of product, as just 
given, has been modified in that respect and to that extent. 

That it was only fair and reasonable to expect considerable 
improvement in the cleanliness and purity of food colors was made 
evident by an examination of two substances sold in the United 
States in large quantities for the purpose of making a very cheap 
red coal-tar coloring matter, which is used in many of the cheapest 
coloring operations, for paints, inks, etc. These substances are 
paranitranilin and betanaphthol. They were found in the United 
States market in such a condition of cleanliness and purity that had 
they been suitable for use in foods no objection could be raised 
against them on these scores. They complied with the requirements 
of the United States Pharmacopoeia with respect to freedom from 
arsenic and all heavy metals, inclusive of iron. The significance of 
this lies in the fact that all the raw materials entering into the manu- 
facture of paranitranilui and betanaphthol also enter into the manu- 
facture of the seven permitted colors of Food Inspection Decision 
No. 76, and that the only source of arsenic in food colors, and probably 
the only way in which iron could be introduced into them, is by way 
of the materials entering into the manufacture of paranitranilin 
and betanaphthol, and since it has been shown to be commercially 
possible to keep those bodies out of paranitranilin and betanaphthol, 
and since there is no occasion whatever for arsenic or iron or other 
heavy metal being present in an}^ of the materials used in the manu- 
facture of the seven permitted colors of Food Inspection Decision 
No. 76, over and above the materials used in the manufacture of para- 
nitranilin and betanaphthol, there was every reason for beUeving 
that the seven permitted colors of Food Inspection Decision No. 76 
could ultimately be manufactured and marketed in the same degree 
of cleanliness and purity that paranitranilin and betanaphthol are 
marketed; in other words, that food colors could be made as clean 
and as pure as paint colors, a condition not existing in the food-color 
market of the United States in the summer of 1907. 

The results of the control exercised by the Department of Agricul- 
ture over the quality of food colors, as compiled in the following 
section, fully justify such expectations, as well as the aim to make 
coal-tar colors when used for food purposes of the same high degree 
of cleanliness and purity as when they are to be used as drugs or as 
they actually are when used for the manufacture of paints and printer's 
inks; that is to say, that the coal-tar color used in a colored food 
should be as clean as the coal-tar color used in making the ink on the 
label of such colored food, the very reverse of the situation existing 
prior to the quality control now established. 



198 



COAL-TAK COLORS USED IN FOOD PRODUCTS. 



XVI. ANALYSES OF CERTIFIED LOTS OF PERMITTED COLORS, 

1909-10. 



TABULATION OF RESULTS, 

The analytical results obtained on 74 batches of certified colors, 
totaling upward of 32,000 pounds, are given in the following tables. 
The analytical results are the work of the New York Food and Drug 
Inspection Laboratory in the course of checking up the analytical 
results certified to in foundation and in supplementary certificates. 
The period covered by these examinations is approximately from 
July, 1909, to January 1, 1910. 

Naphthol Yellow S. 

[Figures calculated to 100 parts pure color and arranged in the order of their size. Figures on the same 
horizontal lines do not refer to the same samples; the dash line shows the location of the average of each 
column.] 





Insolubles. 


Ether extractives. 


Com- 
mon 
salt. 


Sul- 
phur. 


So- 
dium. 


Cal- 
cium. 


Nvunber of batches. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


1 


0.170 
.130 

.097 
.090 

.082 

.079 


0.100 
.078 

.050 
.046 


0.036 
.026 

.024 
.023 

.019 

.018 


0.016 
.007 

.006 
.006 

.005 

.005 


0.067 
.065 

.042 
.038 

.036 


0.088 
.073 

.072 
.064 

.061 

.057 

.056 
.054 


4.06 
2.26 

1.68 
1.41 

1.30 


9.23 
8.99 

8.98 
8.96 

8.89 


13.27 
13.21 


0.13 


2 


.13 






3 - - 


12.92 
12.90 

12.89 

12.89 

12.87 
12.87 

12.81 
12.75 


.05 


4 


.04 






5 


.040 

.036 

.032 
.030 

.010 
.010 








6 


.034 

.031 
.026 

.025 
.025 
.020 
.018 


.63 

.63 

.48 

.47 
.25 
.24 
.19 
.19 


8.86 

8.85 
8.83 

8.71 
8.70 
8.62 








7 


.070 
.060 

.055 
.050 
.050 
.030 
.030 


.016 
.012 

.011 
.010 
.007 
.006 


.004 
.004 

.000 
.000 
.000 
.000 




8 








9 


.048 
.045 
.045 
.045 
.044 




10 




11 




12 






13 
























Average 


.076 
6 

7 


.043 
4 
6 


.017 
6 
6 


.004 
6 
6 


.035 
5 

7 


.051 
8 
5 


1.06 
5 

8 


8.87 
5 
6 


12.93 
2 

8 


.09 




2 


Below 


2 







Ponceau 3R. 

[Figures calculated to 100 parts pure color and arranged in the order of then* size. Figures in the same 
horizontal line do not refer to the same sample; the dash line shows the location of the average of each 
column.] 



Number of 
batches. 


Insoluble. 


Ether extractives. 


Com- 
mon 

salt. 


So- 
dium 

sul- 
phate. 


Sul- 
phur. 


So- 
dium. 


Cal- 
cium. 


Boiling 

point of 

cumi- 

din. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


1 


0.55 
.42 

.41 

.27 


0.29 
.20 

.17 


0.166 
.163 

.161 


0.034 
.033 

.032 


0.019 
.018 

.018 

.018 


0.216 
.213 

.201 

.098 

.073 

.072 
.058 
.057 


5.72 
5.67 

5.57 

5.00 


0.06 
.06 


13.03 
12.99 

12.95 

12.88 


9.51 
9.49 

9.31 

9.31 

9.23 


0.18 
.15 


°(7. 
222-235 


2.. . 


222-235 






3.. 


.00 

.00 

.00 

.00 
.00 
.00 
.00 


.14 
.14 
.12 
.12 


222-235 






4.. 


.12 
.11 

.11 

.09 
.07 


.072 

.053 

.052 
.038 
.038 


.009 

.006 

.002 
.002 
.000 


220-230 






5.. 


.17 

.17 
.16 
.14 
.10 


.017 

.017 
.016 
.014 


4.12 

3.73 
3.71 
3.03 
2.53 


12.80 

12.80 
12.77 
12.64 


220-230 






6 


9.16 
9.12 
9.07 
8.74 


220-230 


7 


220-229 


8.. . - .- 


225-228 


9 


216-226 














Average 

Above 

Below 


.266 
4 
5 


.15 
3 
5 


.093 
3 
5 


.015 
3 

5 


.017 
4 
4 


.124 
3 

5 


4.34 
4 
5 


.01 


12.83 
4 
4 


9.21 
5 
4 


.14 

2 
4 


221-231 
3 
6 











ANALYSES OF CERTIFIED PERMITTED COLORS. 



199 



Orange I. 

[Figures calculated to 100 parts pure color, and arranged in the order of their size. Figures in the same 
horizontal line do not refer to the same sample; the dash line shows the location of the average of each 
column.] 



Number of 
batches. 


Insoluble. 


Ether extractives. 


Com- 
mon 

salt. 


So- 
dium 

sul- 
phate. 


Sul- 
phur. 


So- 
dium. 


Cal- 
cium. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


1 


0.39 

.38 
.28 

.23 

.23 


0.18 

.08 
.08 


0.224 

.220 
.210 

.207 

.181 

.177 

.174 


0.093 

.060 
.043 

.035 

.035 


0.08 

.077 
.067 

.055 


0.360 

.309 
.306 

.300 

.269 

.267 


3.13 

3.13 
3.04 

2.36 


0.22 


9.26 

9.23 
9.12 

9.10 

9.06 

9.06 

9.05 

9.02 


6.82 

6.76 
6.63 

6.62 


0.29 






2 


.10 



.24 


3 


.24 






4 


.05 
.04 
.04 
.03 
.03 
.02 


.22 






5 


.048 
.039 
.036 
.029 
.016 


1.98 

1.91 

1.90 

1.41 

1.05 
1.01 


6.54 
6.48 
6.32 
6.21 


.05 






6 


.16 

.15 

.11 

.10 
.05 


.020 

.018 

.015 

.011 
.011 


.04 






7 


.246 

.224 

.175 
.124 








8 


.124 

.107 
.097 








9 


8.96 
8.15 




10 












Average 

Above 

Below 


.21 
5 

5 


.06 
3 
6 


.172 

7 
3 


.034 
5 
5 


.050 
4 
5 


.258 
6 
4 


2.09 
4 
6 


.03 
1 
1 


9.00 
8 
2 


6.55 
4 

4 


.18 
4 
2 



Amaranth. 



[Figures calculated to 100 parts pure color and arranged in the order of their size. Figures on the same 
horizontal lines do not refer to the same samples; the dash line shows the location of the average of each 
column.] 





Insoluble. 


Ether extractives. 


Com- 
mon 
salt. 


Sul- 
phur. 


Sodi- 
um. 


Calci- 
um. 


Number of batches. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


1 


0.43 
.39 
.29 

.23 

.21 


0.33 
.30 
.19 

.15 

.10 

.10 


0.090 
.088 
.069 

.047 

.042 


0.030 
.017 
.009 

.007 

.007 


0.059 
.017 
.015 

.014 

.012 

.012 

.012 


0.158 
.101 
.100 

.060 


4.18 
4.16 
3.83 

3.73 

3.67 

3.08 

3.02 

2.94 
2.70 


16.04 
15.80 
15.63 

15.61 

15.59 

15.58 

15.57 

15.57 
15.56 

15.54 
15.52 
15.52 
15.52 


14.22 
14.19 
12.10 


0.20 


2 


.19 


3 


.17 






4 


11.47 

11.43 

11.43 

11.42 

11.38 
11.33 

11.32 
11.31 
11.29 
11.27 

11.27 
11.23 
11.21 
11.18 
11.15 
11.14 
11.10 
11.01 


.14 






5 


.056 

.053 

.052 

.051 
.048 

.042 
.042 
.040 
.039 

.038 
.038 
.038 
.035 
.035 
.029 


14 






6 


.13 

.12 

.12 
.12 

.11 
.11 
.11 
.11 

.092 

.09 

.09 

.089 

.08 

.070 

.07 

.04 


.035 

.034 

.034 
.034 

.031 
.031 
.031 
.027 

.026 
.026 
.025 
.021 
.019 
.018 
.012 


.005 

.005 

.005 
.005 

.004 
.004 
.004 
.004 

.004 
.003 
.'002 
.001 
,000 
.000 
.000 


.13 






7 


.06 

.05 
.05 

.04 
.04 
.040 
.036 

.03 

.03 

.025 

.02 

.02 

.02 

.02 


13 






8 


.010 
.009 

.008 
.008 
.007 
.006 

.006 
.005 
.005 
.004 
.003 
.003 


.12 


9 . . 


12 






10 


2.62 
2.21 
2.12 
2.12 

2.04 
1.94 
1.94 
1.91 
1.91 
1.23 
1.22 


12 


11 . . 


11 


12 


09 


13. .- 


09 






14 


15.47 
15.43 
15.41 
15.41 
15.41 
15.40 
15.12 
15.12 


09 


15 


.09 


16 


08 


17 


.07 


18 


.00 


19 




20 


........ 


21 
























Average 


.148 
5 
16 


.083 
6 
14 


.037 
5 
15 


.006 
5 
15 


.011 
7 
12 


.056 
4 
15 


2.63 
9 
11 


15.51 
13 
8 


11.59 
3 

18 


012 


Above 


7 


Below 


11 





200 



COAL-TAR COLOES USED IX FOOD PEODUCTS. 



Light Green SF Yelloivish. 

[Figures calculated to 100 parts pure color and arranged in the order of their size. Figures in the same 
horizontal line do not refer to the same sample; the dash line shows the location of the average of each 
column.] 



Number of 
batches. 


Insoluble. 


Ether extractives. 


Com- 
mon 
salt. 


Sodi- 
um 
sul- 
phate. 


Sul- 
phur. 


Sodi- 
um. 


Calci- 
um. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


1 


0.07 
.045 


0.034 
.02 


0.058 


0.011 
.007 


0.011 
.009 


0.078 


4.15 


0.00 

.00 

.00 
.00 
.00 

.00 


12.69 
12.27 


8.03 

7.99 

7.99 
7.94 
7. 73 


4.52 






2 


.041 

.034 
.033 


.054 

.053 
.042 


.64 

.515 

.43 

.37 


.10 






3 


.03 
.02 
.02 

.01 


.01 
.01 
.01 

.01 


.006 
.000 


.008 
.007 


12.07 
11.88 
11.88 


.09 


4 


.06 




.05 














6 


1.56 


















Average 

Above 

BeloAV 


.033 
2 
4 


.017 
2 
3 


.041 
1 
3 


.006 
2 

2 


.008 
2 
2 


.056 
1 
3 


1.221 
1 

4 


.00 




12.16 
2 
3 


6.87 
5 
1 


.96 
1 
4 



Erythrosin. 

[Figures calculated to 100 parts pure color and arranged in the order of their size. Figures in the same hori- 
zontal line do not refer to the same sample; the dash line shows the location o the average of each column. J 





Insoluble. 


Ether extractives. 


Com- 
mon 
salt. 


Sodi- 
um 
sul- 
phate. 


Sodi- 
um. 




Number of batches. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


lodin. 


1 


0.13 
.09 


0.09 

.04 


0.039 
.039 

.037 


0.017 
.009 

.008 




0.051 

.048 

.047 


1.13 
1.00 

.48 


0.00 
.00 

.00 

.00 
.00 
.00 

.00 
.00 
.00 


5.42 
5.35 

5.33 

5.29 
5.15 
5.11 


57.45 


2 


56.46 






3 


.059 

.05 
.04 
.04 

.04 
.03 


.024 

.01 
.01 
.01 

.01 


56.40 






4 


.034 
.033 
.033 

.027 


.002 
.002 
.000 


.037 
.035 
.035 

.027 


.23 
.09 
.09 

.09 
.09 
.036 


56.07 




55.98 


6 .. -. 


55.97 






7 


3.85 


55.94 


8 








55.90 


9 












55.88 


















Average 


.059 
2 
6 


.028 
2 
5 


.035 
3 

4 


.006 
3 
3 




.040 
3 
4 


.360 
3 
6 


.00 


5.07 
6 

1 


56 23 


\bove 


3 


Below 


6 







Indigo disulpho acid. 

[Figures calculated to 100 parts pure color and arranged in the order of their size. Figiu-es on the same hori- 
zontal lines do not refer to the same samples; the dash line shows the location of the average of each 
colmnn.] 



Number of 
batches. 


Insoluble. 


Ether extractives. 


Com- 
mon 
salt. 


Sodi- 
imi- 
sul- 

phate. 


Sul- 
phur. 


Sodi- 
um. 


Calci- 
um. 


Total. 


Inor- 
ganic. 


Neu- 
tral. 


Alkali. 


Acid. 


Total. 


1 


0.50 
.46 
.45 


0.28 
.26 
.25 
.24 


0.140 

■ 

.134 


0.087 
.061 


0.099 


0. 320 
.217 


6.77 

3.60 

3.21 

2.89 

1. 85 
.40 


16. 12 
10.22 


13.45 
13.43 
13.42 
13.39 


10. 13 
9.90 
9.64 
9.60 


0.45 






2 


.038 
.026 
.024 
.016 


. 13 






3 


.102 
.088 
.075 


.029 
.015 
.013 


.143 
.141 
.126 


4.79 

.00 

.00 
.00 


. 13 






4 


.43 

.42 
.32 


.05 






5 


.22 
.16 


13.22 
13.15 


9.13 
8.54 




6 
















Average 

Above 

Below 


.43 
3 
3 


.235 
4 
2 


.108 
2 
3 


.041 
2 
3 


.041 

1 
4 


.189 
2 
3 


3.12 
3 
3 


5.19 
2 

4 


13.34 
4 
2 


9.49 
4 

2 


.19 
1 
3 



ANALYSES OF CERTIFIED PERMITTED COLORS. 



201 



C020>ARISON WITH ANALYSES MADE IN 1907. 

A comparison, as far as possible, of these figures with the corre- 
sponding data previously given for samples on the market in the 
summer of 1907 is made in the following table. The figures in this 
new table show the value of the fraction obtained by dividing the 
old average figure by its corresponding new average figure — that is, 
they show how many times greater the old average figures are than 
the corresponding new average figures. Italics indicate those items 
in which there has been a retrogression in the new figures as com- 
pared with the old; all the other figures represent an advance. It 
will be noted that comparisons are not made for Ponceau 311 and 
Erythrosin. This comparison was omitted because there was but 
one sample of Ponceau BE, examined and a partial analysis of one 
sample of Erythrosin in the old work. 

Ratio of average figures of 1907 to those for the certified colors, 1909. 





Salt. 


Insoluble. 


Ether extracts. 


Color. 


Total. 


Volatile. 


Nonvol- 
atile. 


Nonacid. 


Acid. 


Total. 


Naphthol Yellow S 


4.88 
3.54 
15.07 
.66 
8.05 


4.44 

9.07 

n.26 

31.00 

3.29 


9.02 
20.60 
21.40 
29.00 

5.4 


0.67 
3.00 
7.71 
17.00 
1.56 


7.50 

1.57 

4.07 

.65 

.15 


21.89 
4.53 

10.77 
6.25 
3.48 


15.97 


Orange 


2.26 


Amaranth 


5 00 


Green 


1.67 


Blue... 


.68 







These retrogressions are : 

1. Salt in the Green. 

2. Nonvolatile insolubles in the Yellow. 

3. Nonacid ether extract in the Green. 

4. Nonacid ether extract in the Blue. 

5. Total ether extract in the Blue. 

With respect to the first of these retrogressions there is this to be 
said: One lot of Green had apparently been purified by precipitation 
with salt, since it was in every other respect of a high quality — that 
is, it was free from arsenic and heavy metals within the pharmacopceial 
test, and its ether extractives were very satisfactory. The other lots 
of Green examined had apparently not been made in this manner. 

With respect to the second retrogression, the probable explanation 
is that some of the lots were made during a period when the municipal 
water supply was excessively hard, as before explained. The remain- 
ing three retrogressions are probably due to the fact that the old 
methods of analysis used were not so accurate as the methods later 
employed and hereinafter described (pp. 223, 225). 

It will be noted that in three of the six batches of Indigo disulpho 
acid reported there is no sodium sulphate; whereas in the other three 
batches the amount of this substance is as high as 16.12. The reason 
for this is that in the early stages of the work the results obtained 



202 



COAL-TAR COLOES USED IN FOOD PRODUCTS. 



by the manufacturers pointed in the direction of the impossibility of 
getting rid of all the sodium sulphate; but later and more extended 
work showed this conclusion to be an error. There is therefore no 
good reason for permitting sodium sulphate as a contaminant in this 
or any other of the seven products. 

CONFORMITY OF ANALYTICAL DATA WITH THEORETICAL COM- 
POSITION. 

The seven tables following, likewise based upon the 74 Govern- 
ment analyses, show the conformity or nonconformity, as the case 
may be, of these samples with their theoretical composition. The 
second and third columns show the percentage based on theory of 
the contained sulphur and sodium in the case of all colors except 
Erythrosin, where the figures for iodin are substituted for those of 
sulphur. The fourth column shows the actual ratio of sodium to sul- 
phur or iodin, as the case may be, and the fifth column gives the 
percentage of the figure of column 4 based on the theoretical value 
which is given in parentheses at the head of columns 4 and 5. The 
summary gives the maximum, minimum, and average of each column. 
Taken as a whole the figures are fairly satisfactory and show a rea- 
sonable conformity of the actual product to theoretical requirements, 
although there seems to be considerable room for improvement, which 
no doubt can be achieved in time. 

Percentages based on theoretical composition. 

NAPHTHOL YELLOW S. 



Number 
of 


Sulphur, 


Sodium. 


Na 

-g-= (1.4379). 


Number 

of 
batches. 


Sulphur. 


Sodium. 


Na 
-S-=(L4379). 


batches. 


Value. 


Per cent. 


Value. 


Percent. 


1. 


Per cent. 
103. 120 
96. 312 
97. 205 
97. 542 


Per cent. 
103. 10 

99. 068 
100. 000 

99. .534 


1. 4377 

1. 4791 

1. 4792 
1. 4707 


99.983 
102.860 
102.870 
102. 270 


10 

11........ 

12 

13 


Per cent. 

98.880 

98. 658 

100.330 

100. 100 


Per cent. 
101.06 
101. 22 
100. 15 
100.00 


1.4576 
1.4631 
1. 4353 
1. 4363 


101 36 


2 


101. 74 


3 . 


99 826 


4 


99.890 


5 


Average.. 
Max.. ... 
Mia 




6 










99. 101 

103. 120 

96.312 


103. 212 
103. 500 
99.068 


1. 4578 
1.4792 
L4353 


101. S7S 


7 


98. 992 
99. 331 
100. 440 








102. 87 


8 


100. 15 
103. 50 


1.4498 
1. 4692 


100. 80 
102. 18 


99.826 


9 









PONCEAU 3R. 



Number 
of 


Sulphur. 


Sodium. 


Na 

-g-= (0.71905). 


Number 

of 
batches. 


Sulphur. 


Sodium. 


^g?'= (0.71905). 


batches. 


Value. 


Per cent. 


Value. 


Per cent. 


1 

2 


Per cent. 
97. 454 


Per cent. 
93. 617 
03.927 
97. 749 
98. 174 
97.095 
09. 783 
99.783 


0. 69138 


96. 173 


8 

9 

Average . 

Max 

Min 


Per cent. 
98. 693 
99. 308 


Per cent. 
101.920 
101.700 


0. 74296 
. 73679 


103.33 
102. 48 




100. 4G0 
100. 140 
98. 458 
99. 841 
98.093 


. 69992 
.70518 
. 70930 
.71892 
.72730 


97.351 
98. 080 
98.662 
99. 918 
101. 10 




4 

5 

6 

7 


99. 256 
100.46 
97.454 


98.738 
101.920 
93.617 


.71648 
.74296 
.69138 


99.144 
103.33 
96. 173 



ANALYSES OF CEKTIFIED PEEMITTED COLORS. 



203 



Percentages based on theoretical composition — Continued. 

ORANGE I. 



Number 
of 


Sulphur. 


Sodium. 


^=(0.71905). 


Number 

of 
batches. 


Sulphur. 


Sodium. 


Na 
-g-=(0.71905). 


batches. 


Value. 


Per cent. 


Value. 


Per cent. 


1 

2 

3 

4 

5 


88.972 
100. 76 
101.09 
99. 135 
99. 135 
97. 816 
98.799 


100.44 
103. 72 
102. 53 


0. 81226 
.73889 
.73002 


112.97 
102. 77 
101. 53 


8 

9 

10 

Average . 

Max 

Min 


98.471 
99. 563 
99.342 


85.901 
99.241 
98.330 


0. 70066 
.71710 
. 71208 


97.454 
99.740 
99.042 








98. 308 
101. 09 
88. 972 


99.376 

103. 72 

95.901 


.72957 
.81226 
.69309 


101. 475 


6 

7 


94. 234 
100.610 


. 69309 
. 73243 . 


96. 391 
101. 90 


112. 97 
97.454 



AMARANTH. 



96.795 


105. 76 


0. 78519 


98. 176 


99. 037 


. 72488 


94.975 


124.29 


.94048 


94. 975 


124.04 


. 93849 


100.750 


96.240 


. 68637 


99. 246 


99. 911 


.72341 


97. 174 


100. 260 


. 72454 


96.929 


99.827 


.74011 


97.926 


97. 465 


. 71520 


96. 975 


97. 990 


.72744 


96.733 


97. 389 


.72338 


97.487 


98. 514 


. 72615 


96. 798 


97.028 


.72030 



109. 21 
100. 82 
130. 80 
130. 53 

95. 470 
100. 62 
100. 78 
102. 94 

99. 476 
101. 18 
100. 62 
100. 99 
100. 18 



15 

16 

17 

18 

19 

20 

21 

Average 

Max 

Min 



97.800 


98.863 


0. 72640 


97. 499 


99. 911 


. 73646 


97. 614 


98. 950 


.72843 


97. 499 


99. 476 


. 73325 


97. 863 


98. 689 


.72465 


98.052 


98.393 


. 72106 


97.800 


98. 514 


. 72383 


97.735 


97.725 


.71852 


97. 467 


101.347 


.74707 


100. 750 


124.29 


.94048 


94. 975 


96. 240 


.686.37 



101. 03 
102. 43 
101. 32 
101.98 
100. 78 
100.05 
100. 68 
99.914 



103.90 
130.80 
95. 470 



LIGHT GREEN SF YELLOWISH. 



1 


102.85 








6 

Average . 

Max 

Min 


104. 50 


95. 547 


0. 65783 


91 495 




96. 148 
93. 018 
96. 629 
96. 148 








3 

4 

5 


109. 87 
106. 23 
102.35 


0. 60911 
. 65358 
.67256 


84.722 
90. 911 
93.540 


105. 26 
109. 87 
102. 85 


95.498 
96. 029 
93.018 


.64827 
?67256 
.60911 


90. 167 
93. 540 
84. 722 



ERYTHROSIN. 



Number 
of 


lodin. 


Sodium. 


5^= (0.090855). 
I2 


Number 

of 
batches. 


lodin. 


Sodium. 


Na 

Y^= (0.090855). 


batches. 


Value. 


Per cent. 


Value. 


Per cent. 


1 

2 

3 

4 

5 


Per cent. 
96.915 
97.051 
99.593 
97. 780 
97.209 
96.983 
97.035 


Per cent. 
73. 473 
100.94 
98.277 
97.521 


0. 068873 
. 094497 
. 089G39 
.090604 


75.805 
104.00 

98. G63 
99. 724 


8 

9 

Average . 
Max.. .. 
Min 


Per cent. 
96.879 
97. 886 


Per cent. 
102.09 
103.43 


.095741 
.095995 


105. 37 
105. 65 


97.952 
99.593 
96. 879 


96.777 
103.43 
73. 473 


.090204 
.095995 
.068873 


99. 146 
105.65 


6 








75.805 


7 


101.71 


.095229 


104.81 





204 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

Percentages based on theoretical composition — Continued, 

INDIGO DISULPHO ACID. 



Number 
of 


Sulphur. 


Sodium. 


^^=(0.71905). 

b 


Number 

of 
batches. 


Sulphur. 


Sodium. 


^^=(0.71905). 


batches. 


Value. 


Per cent. 


Value. 


Percent. 


1 

2 

3 

4 

5 


Per cent. 
97.670 
95.636 
97.600 
96. 148 
97.382 


Per cent. 
103. 330 

98.279 
103. 760 

91.926 
106.560 


0.71482 
.69430 
.71832 
.64598 
.73934 


99.423 
95.669 
99.910 
89.848 
102.830 


6 

Average . 

Max 

Min 


Per cent. 
97.818 


Per cent. 
109. 040 


. 75315 


104. 750 


97.042 
97.818 
95. 636 


102. 149 
109.040 
91.926 


.71099 
.75315 
.64598 


98. 738 
104.750 
89.848 



ARSENIC DETERMINATIONS ON 86 BATCHES. 

During the course of this work it became necessary to determine 
the exact amount of arsenic contained in 86 of the various batches 
of certified colors ; for this purpose the arsenic method of Seeker and 
Smith (see p. 212) was devised. These results are expressed in the 
number of parts of color containing one part of metallic arsenic (As). 
The numbers in parentheses indicate the number of specimens of the 
quality indicated. 

Naphthol Yelloiu S (17 specimens).— 770,000, 833,000, 1,250,000 (2), 1,428,000 (2), 
1,666,000 (3), 2,000,000 (6), 3,333,000 (2). 

Ponceau (15 specimens).— 588,000, 625,000, 667,000, 714,000 (2), 769,000 (2), 
1,000,000 (2), 1,111,000, 1,250,000, 1,666,000 (2), 2,000,000, 2,500,000. 

Orange (7 specimens).— 200,000, 250,000, 588,000, 1,000,000, 1,111,000, 1,429,000, 
5,000,000. 

Amaranth (27 specimens).— 909,000, 1,000,000, 1,111,000, 1,250,000 (2), 1,438,000 (3), 
2,000,000(4), 2,500,000 (4), 3,333,000 (9), 5,000,000 (2). 

Green (8 specimens) .—166,000, 200,000, 370,000 (2), 500,000, 666,000, 770,000, 833,000. 

j;r2/«/irosm (7 specimens). —2,000,000 (2), 5,000,000 (2), 10,000,000 (2), 20,000,000 (1). 

Blue (5 specimens).- 285,000, 666,000, 1,428,000, 3,333,000 (2). 

The United States Pharmacopoeia test for arsenic is sensitive to 
0.005 mg of arsenious oxid (AS2O3) which on a sample containing 2 
grams of actual or real color would amount to one part of arsenious 
oxid in 400,000 of color; calculated to metallic arsenic, the basis 
employed in the foregoing, this would mean 528,000 parts of color for 
each one part of metallic arsenic. 

There are, therefore, in the foregoing 86 lots of certified colors 
8 wliich did not comply with that requirement, namel}^: 

Orange (2 specimens).— 200,000 and 250,000. 

Green (5 specimens).— 166,000; 200,000; 370,000 (2); 500,000. 

Blue (1 specimen).— 285,000. 

The reason for this discrepancy is that in the preparation of the 
samples for analysis by the United States Pharmacopoeia test a loss 
of arsenic ensued, which is avoided in the Seeker-Smith method 
now employed in making these' determinations. Had the existence 



ANALYSES OF CEETIFIED PEEMITTED COLORS. 205 

of this discrepancy been proven at the time the first analysis was 
made certification would have been denied to the eight lots above 
mentioned. 

These results further show the position taken early in the work 
by several of the manufacturers — that a requirement of not more 
than 1 part of metallic arsenic in not less than 264,000 parts of 
coal-tar color could not be comphed with on a commercial scale — 
to be imtenable; on this basis only 4 out of the 86 lots examined 
would have been excluded. Further, the position of some manu- 
facturers and dealers that the arsenic requirement ought, for prac- 
tical manufacturing reasons, not to be more rigorous than one part 
of metallic arsenic in 26,400 parts of color, or 1 part of arsenious 
oxid (AS2O3) per 20,000 parts of color, is not borne out by the data. 

SUGGESTED REQUIIIEMENTS FOR CERTIFIED COLORS. 

Although the material embodied in this report gives a very good 
idea of the composition and quality of substantially 30 different 
lots of permitted colors prior to the issuance of Food Inspection 
Decisions Nos. 76 and 77, and of 74 lots of certified colors, yet these 
data are hardly sufficient to furnish a basis for standards with which 
each color specimen must comply in detail. The fitness or unsuit- 
abifity of any lot has been determined by the examination of the 
analytical data obtained thereon in the Food and Drug Inspection 
Laboratory at Nev/ York; such examination has been appHed to 
the particular color under investigation with respect to its general 
relationship to the results theretofore achieved. If in some minor 
quaHty, as, for example, freedom from salt, the sample was not up to 
what had been previously accomplished, but in a major quality, as 
for example, ether extractive, it was equal to or better than what 
had been previously accompHshed, and the pharmacopoeial tests for 
arsenic and heavy metals were satisfied with the exception of iron, 
and the amount of iron was mthin the limit previously stated, 
0.005 per cent, and the other factors showed a fairly close conformity, 
such a defect as its salt content would not act as a bar to the pass- 
ing of the lot; however, no matter how good a color might be in 
respect to such determinations as ether extractive, if it failed to 
comply with the United States Pharmacopoeia requirement for 
arsenic or for heavy metals it was not accepted. 

These arsenic results have been tabulated to show the distribution 
of arsenic content (AS2O3); the numbers at the top are the Green 
Table numbers; the numbers in the body of the table indicate the 
number of specimens of the arsenic content stated in the first column ; 
the last column shows the totals of all colors of the arsenic content 
(AS2O3) corresponding thereto. 



206 



COAL-TAK COLORS USED IN FOOD PRODUCTS. 
Arsenic content of 86 lots of certified colors. 



Arsenic 
content. 


Green Table numbers. 


Total. 


4 


56 


85 


107 


435 


517 


692 


1 part in— 

1126,200 

1 151, 000 

1 151, 500 

1189,300 

1215,900 

1280,300 

1 378, 700 

445, 400 

473, 500 

504, 600 

505,300 

540, 900 

582,500 

583, 300 

631,000 

688,700 

757,500 

841, 600 

946, 900 

1,081,000 

1,082,000 

1,089,000 

1,262,000 

1,515,000 

1,893,000 

2,524,000 

3,787,000 

7,157,000 

15,150,000 










11 






1 
1 
1 
1 
1 
2 
1 
2 
1 
2 
1 
2 
2 
2 
2 
1 
4 
3 
5 
3 
1 
3 
5 

13 
5 

13 
5 
2 
1 


















11 
11 






























11 










12 
11 



















1 

1 


1 




















1 




1 


1 


1 

2 
2 






























1 
1 




















1 
1 
1 
2 






'"2" 

2 


2 
1 

1 


1 
1 
























1 




1 












3 








3 

6 
"2" 


2 

1 
1 












4 
4 
9 

2 




2 








2 




1 




2 
2 

1 


























17 


15 


7 


27 


8 


7 


5 


86 



1 The certification of these lots was due to an unknown source of error in the analytical method; the 
analyses made at that time (July, 1909), showed less than 1 part of AS2O3 per 400,000; see also page 204. 

It is therefore somewhat premature to attempt to define rigidly 
the requirements for composition and purity for colors imtil a suffi- 
cient number of analyses is available to permit a hard-and-fast Hne 
to be drawn for each item as required for each color. Until that 
time the decision as to whether or not a certain color shall be cer- 
tified must rest with the Department of Agriculture. However, 
the following requirements are tentatively suggested as being com- 
mercially practicable. It should be clearly understood that the ten- 
tative requirements here stated are based on the results of actual 
control, and are not any more searching or numerous than are the 
requirements for many if not most of the coal-tar dyes or their com- 
ponent parts in the industrial arts, particularly for the various kinds 
of paint, varnish, and ink making. While it may be that some of the 
tentative requirements herein defined necessitate the expenditure of 
considerable work and time, yet that is also true of some of the 
commercial requirements. Since manufacturers of cheap paints, 
varnishes, inks, and the like, find it wise and necessary carefuUy to 
control the quafity of the coal-tar dyes or their component parts 
which they use, it can not be less wise or necessary to extend the 
same kind of quality control to those coal-tar dyes intended and sold 



ANALYSES OF CERTIFIED PEEMITTED COLORS. 



207 



for human consumption as food. This stand is fully justified by the 
quality of the coal-tar dyes offered as food colors on the United States 
markets as described in the foregoing pages. That such control is 
not only practical, but practicable, is fully proved by the fact that 
more than 20.5 tons (41,000 pounds) of coal-tar food dyes have been 
so controlled, examined, and certified under the food inspection deci- 
sions hereinbefore mentioned. 

The figures are expressed in parts per hundred of actual color 
contained in the dye and not in parts per hundred of the total 
substance. The numbers at the head of the columns are the num- 
bers in the Green Tables. 

Tentative limits of composition suggested for permitted colors. 
(Parts per hundred of actual color.) 



Determinations. 


Green Tables numbers. 


4 


56 


8.5 


107 


435 


517 


692 


Insolubles: 

Total 


0.070 
.040 

.017 
.004 
.050 
.600 


0.270 
.150 

.090 

.015 

.017 

5.000 


0.250 
.050 

.150 

.035 

.050 

2.000 


0.130 
.050 

.030 

.005 

.010 

2.500 


0.030 
.010 

.040 
.006 
.008 
.600 


0.060 
.020 

.035 
.002 


0.450 




.250 


Ether extractives: 
Neutral 


.100 


Alkaline 


.030 


Acid 


.150 




3.000 







In addition to these there are the following requirements applicable 
to all colors : 

1. The absence of admixed dye must be convincingly demonstrated by suitable 
test. 

2. Arsenic. — ^Test 17 of the United States Pharmacopoeia, 1900, applied to so much 
of the specimen as represents 3.5 grams of actual dye must give a negative response. 
Such negative result must be reenforced by a check test identical with the test on the 
dye with the addition of 0.005 mg of arsenic (AS2O3) to the dye prior to treatment, 
and this check test must produce a positive result for the presence of arsenic. Igni- 
tions in the preparation of the material for the test must be made in porcelain. 

Any other mode of testing which is demonstrated to be capable of detecting 0.005 
mg added arsenic (AS2O3) in so much of the specimen as represents 3.5 grams of actual 
color will, of course, be accepted. This quantity, however, is only tolerated tenta- 
tively pending further investigations relative to the complete, or practically com- 
plete, elimination of arsenic from foods, especially those which are largely used by 
children, such as candies. 

3. Heavy metals. — ^Test 121 of the United States Pharmacopoeia as revised May 1, 
1907, using so much of the specimen as represents one part of actual dye must give a 
negative response for all metals except iron, which may be present in amounts not hi 
excess of 0.005 per cent of iron based on the dye actually present in the specimen. 

4. None of the dyes offered for certification shall contain any Glauber's salt or 
sodium sulphate in any form, nor shall they contain any added sugar, dextrin, or 
other loader, filler, or reducer for any purpose whatsoever, and convincing proof of the 
absence of any or all of them must be submitted. 



208 COAD-TAR COLORS USED IN FOOD PRODUCTS. 

5. The ether extractives are to be made successively upon water solutions of the 
dye, first neutral, then made alkaline with caustic soda, and then made acid with 
hydrochloric acid, using washed or sodium, dried ether. 

6. The sulphur content of the sulphur-containing dyes must agree substantially 
with the theoretical ; likewise the sulphated ash figures of all must agree substantially 
with the theoretical; variations between these two sets of figures, as long as they are 
consistent with each other, will not be reason for rejection. 

7. In the case of No. 4 proof must be submitted showing that the specimen is of the 
sodium or potassium variety, and if it is a mixture of these two varieties the proportion 
of each present in the mixture must be stated. 

8. In the case of No. 56 the crude cumidin employed may have a boiling point of 
from 220° to 230° C, and may be liquid or solid; the absence of any compound of 
S or G salt must be convincingly shown. 

9. In the case of No. 85 convincing proof must be submitted that beta-naphthol 
orange if present at all is present in an amount not in excess of 5 per cent of the coal- 
tar dye present. 

10. In the case of No. 107 the absence of any compound of S or G salt must be 
convincingly shown. 

11. In the case of No. 435 the product should be free from calcium; convincing proof 
of absence of No. 434 must be submitted. 

12. In the case of No. 517 the actual dye must contain not less than 56 per cent of 
iodin (sodium basis) and must not contain any other halogen; the kind and amount 
of metallic base, whether sodium, potassium, or the like, must be shown. 

13. In the case of No. 692 the absence of indigo monosulphonic acid and of nonsul- 
phonated indigo must be convincingly shown. 

14. Each foundation certificate must be filed in duplicate, but need not be executed 
in duplicate and must contain a summarized or tabulated statement of all the quan- 
titive results contained in the certificate, also a tabulation or summary of the quali- 
tative tests made, together with the results of such tests, all stated on one sheet, so 
that the certificate will bear within itself its own summary and conclusions. 

15. The fundamental analytical data must be given with such fullness as to permit 
efficient checking of the calculations, and the arithmetical operations performed 
should be indicated wherever needful to avoid confusion, or to facilitate the work of 
the checking chemist, or make the meaning of the certificate more plain. 

There are freely quoted in the United States market two substances, 
paranitranilin and betanaphthol; which are subject to much com- 
petition, the prices for which, wholesale, are not far from 25 cents 
and 9 cents, respectively. A specimen of each has been exaniined, 
and, as before stated, they have both been found to be of such 
purity, with respect to arsenic, heavy metals, and general cleanliness, 
that had they been capable of use in food products, no objection 
against their use on this score could reasonably be raised; certainly 
no such objection could be successfully maintained. 

The following table discloses the chemicals entering into the manu- 
facture of paranitranilin and of betanaphthol, as well as of each 
of the seven permitted colors; the ingredients numbered 1 to 7 are 
used in the manufacture of these two substances, as well as in the 
seven permitted colors, as indicated by the '^x" entries; ingredients 
8 to 20 are used only in the manufacture of the seven permitted 
colors, and not in paranitranilin and betanaphthol. 



ANALYSES OF CERTIFIED PERMITTED COLORS. 



209 



Comparison of chemicals entering into the composition of the seven permitted colors and 
of paranitranilin and betanaphthol. 



Determinations. 


4. 

Nap- 

thol 

Yellow 

S. 


56. 

Pon- 
ceau 
311. 


85. 
Orange 


107. 

Ama- 
ranth. 


435. 

Light 
Green. 


517. 
Ery- 
thro- 
sin. 


692. 
Lidigo 
disul- 

pho 
acid. 


Parani- 
trani- 
line. 


Beta- 
naph- 
thol. 


1. Naphthalene 


X 


X 
X 
X 
X 
X 
X 
X 


X 
X 
X 
X 
X 
X 
X 


X 

X 
X 


X 
X 
X 
X 
X 


X 


X 
X 
X 


X 
X 
X 
X 

X 


X 


2. Benzol 






X 
X 


X 


4. Nitric acid 




5. Metallic iron .... 












X 


X 
X 




7. Caustic soda or potash . . . 


X 


X 


8 Carbonate of soda 


X 
X 


X 
X 

X 
X 
X 
X 


X 
X 


X 
X 


X 


X 
X 


X 
X 












10 Wood or methyl alcohol 






11. Lime 




X 
X 


X 
X 


X 


X 






12. Hydrochloric acid 








1.^. RndliTm nitritfi . 














14. Ethyl chlorid 




X 

X 

X 










15. Peroxid of lead or of 
manganese. . 


















16. Phosgene 


















17. lodin 










X 
X 
X 









18. Metallic mercury 












X 






19. Ferric chlorid 
















20. Chlorin 












X 


























6 


13 


11 


11 


10 


9 


10 


5 


3 



With respect to the arsenic content of the finished product, it can 
be asserted, without any fear whatever of successful contradiction, 
that the arsenic finds its way into the goods by way of the sulphuric 
acid which is used in the manufacture of all the permitted colors, as 
well as in the manufacture of Paranitranilin and Betanaphthol. If 
arsenic from this source can be kept out of these substances it can 
also be excluded from the permitted colors. 

Turning now to those ingredients below the parallel lines, the only 
means of introducing arsenic would be through the hydrochloric acid 
used, which in turn derives its arsenic from the sulphuric acid used 
in its manufacture, and since arsenic free-sulphuric acid can be used 
in the first stages of producing the seven permitted colors and the 
paranitranilin and betanaphthol, it can also be employed in the manu- 
facture of the hydrochloric acid used in the subsequent stages of 
manufacture of the seven permitted colors. Therefore, it seems 
unreasonable to permit a higher arsenic content in food colors than 
in paranitranilin and betanaphthol, which are sold in open com- 
petition, and which are used for the production of the very cheapest 
colored cloths, inks, and paints. 

With reference to the content of iron, and other heavy metals, 
which satisfied the pharmacopoeial tests in the case of paranitranilin 
and betanaphthol, these materials probably enter the product from 
the vessels in which the manufacturing operations are performed. 
The same kind of vessel used in the manufacture of paranitranilin 
97291°— BuU. 147—12 14 



210 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

and betanaphthol is used in making the seven permitted colors, and 
since the heavy metals can be and are kept out of these two substances 
to the extent required by the Pharmacopoeia, there seems to be no 
good reason why they should not be kept out of the seven permitted 
colors when made for use in food products. 

Since all these defects in the seven permitted colors can be obviated 
in their first stage of manufacture (as is shown in the case of para- 
nitranilin and betanaphthol, and in some actual commercial samples 
of 1907, see sections XIV and XV), they are commercially avoidable 
at subsequent stages of manufacture, and there is no good reason why 
they should be then introduced. 

XVII. METHODS OF ANALYSIS USED IN TESTING COLORS FOE 

CERTIFICATION. 

INTRODUCTION. 

The exact analytical methods developed and tested in the New 
York Food and Drug Inspection Laboratory and used in obtaining 
the analytical data contained in the preceding chapter are described 
in the following pages. These descriptions were written by A. F. 
Seeker, of that laboratory, under whose immediate supervision all the 
laboratory work was done, and they represent a great deal of work, 
extending over more than three years. The methods are submitted 
in the hope and expectation that in their wider application by a larger 
number of chemists any defects in the methods or conclusions drawn 
from the results will be detected and rectified. Experience in the 
New York laboratory has shown that even different chemists of 
varying degrees of experience in this particular line of work obtain 
concordant duplicates after a comparatively short laboratory 
acquaintance with these methods. 

The identity of these colors and their freedom from foreign dyes is 
shown by the close agreement of their elements, as determined by 
analysis, with their theoretical composition; their behavoir toward 
reagents as given by standard works on dyes; their distribution 
between the layers when neutral, alkaline, and acid aqueous solutions 
are shaken with various immiscible solvents; uniformity of shade in 
the spots produced by particles of the dry color blown over the surface 
of wet filter paper, or water, and over concentrated sulphuric acid; 
uniformity of shade produced by a 0.5 per cent dyeing on wool under 
standard conditions, with similar dyeings from fractions produced by 
partial precipitation, by partial salting out, by fractional crystalliza- 
tion, and by extraction with alcohol or some liquid in which the pure 
color is not very soluble; and the behavior of the dye in acid and 
alkaline solution toward cotton. Which of these tests are needed to 
prove conclusively the identity of certain dyes or to establish their 



METHODS OP ANALYSIS FOR CERTIFIED COLORS. 211 

absence, is a matter that varies so much from case to case that it must 
be left largely to the individual judgment to decide on the best com- 
bination of tests, and for that reason such combinations are not here 
offered. The general methods and procedures just outlined have, 
however, when properly combined, led to satisfactory results. 

In order to compare the results of the color analyses on the same 
basis, the actual figures obtained in the various determinations 
besides being reported as found, are also recalculated on a basis of 
100 parts of actual color, i. e., the sum of the percentages of material 
which is not coloring matter, such as moisture, total insoluble matter, 
sodium chlorid, sodium sulphate, and ether extractives is deducted 
from 100 and the percentages of the various constituents found 
divided by the difference, the quotient being then multiplied by 100. 
The percentage of sodium in actual dye is calculated from the sul- 
phated ash. The methods of analysis of the seven permitted colors 
of Food Inspection Decision No. 76 are given in the following order: 



1. Naphthol Yellow S. 

2. Ponceau 3R. 

3. Orange I. 

4. Amaranth. 



5. Light Green S F Yellowish. 

6. Erythrosin. 

7. Indigo Disulphoacid. 



NAPHTHOL YELLOW S. 
MOISTURE. 



Dry from 1 to 2 grams of the finely powdered dye in an air oven at 
120° to 125° C. to constant weight. 

TOTAL INSOLUBLE MATTER. 

Dissolve 5 grams of color in 200 cc of hot distilled water, filter 
through a tared gooch, wash till the washings run through colorless, 
dry the insoluble residue at 105° C, and weigh. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 

Ignite the gooch containing the insoluble matter of the last deter- 
mination at a low red heat, cool, and weigh. 

SODIUM CHLORED. 

Dissolve 3 to 5 grams of dye in 200 cc of water, acidify the solution 
with nitric acid, and precipitate the chlorin as silver chlorid. Tlie 
latter is separated, washed, ignited, and weighed in a tared gooch 
crucible in the usual way. 

SODIUM SULPHATE. 

Dissolve 1 gram of dye in about 100 cc of water in a 200-cc gradu- 
ated flask, add 40 cc of a 20 per cent solution of potassium chlorid, 
shake the mixture well, make up to mark with water, shake again, 



212 COAL-TAE COLORS USED IN FOOD PEODUCTS. 

and then filter through dry paper. Treat 100 cc of the filtrate (repre- 
senting 0.5 gram of dye) with 5 cc of 10 per cent barium chlorid solu- 
tion without acidifying, and allow to stand overnight. If a precipi- 
tate forms, it is filtered, washed, ignited, and weighed in the usual 
way. 

HEAVY METALS. 

Treat the sulphated ash from 1 gram of the sample with 20 cc of 
water, digest with 10 cc of 10 per cent hydrochloric acid till solution 
is complete, place 3 cc of the mixture in a test tube, add 10 cc of freshly 
prepared hydrogen sulphid test solution (U. S. P.), shake the mixture, 
warm to 50° C, stopper, and allow to stand in a warm place (at about 
35° C.) for half an hour. Run a blank test at the same time, with 
the same amount of hydrogen sulphid solution, using water instead 
of the solution containing the color ash. No turbidity other than 
that sometimes produced by slight separation of sulphur should 
appear in this test. Both tubes are then made slightly alkaline 
with ammonium hydroxid, and no precipitate should be produced, 
although a slight coloration, due to the presence of a small amount 
of iron, sometimes occurs. If this coloration is very marked the 
amount of iron should be determined. This is done by digesting the 
sulphated ash from a weighed amount of the sample with hydrochloric 
acid until all of the iron has gone into solution. The solution is 
filtered, and the filtrate poured into an excess of hot, pure, freshly 
prepared sodium hydroxid (by sodium) solution in a platinum dish. 
The precipitate is washed, dissolved in dilute hydrochloric acid, and 
again precipitated with ammonium hydroxid. The last precipitate 
is washed, ignited, and weighed in the usual manner. 

ARSENIC (seeker AND SMITH's METHOd). 

Dissolve 10 grams of the dye in 200 cc of water, heating to insure 
complete solution of the color, add about 10 cc of strong bromin water 
to convert any arsenite to arsenate. Make the mixture alkaline 
with a few cubic centimeters of strong ammonium hydroxid. 
Twenty cubic centimeters of a sodium phosphate solution containing 
100 grams of crystallized sodium phosphate per liter are next added 
from a pipette, after which magnesia mixture (containing 55 grams 
of hydrated magnesium chlorid, 55 grams of ammonium chlorid, 
and 88 cc of ammonium hydroxid, specific gravity 0.9 per liter) is 
added from a burette, stirring vigorously. The amount of mag- 
nesia added should be in slight excess of that necessary completely to 
precipitate the phosphate and should previously be ascertained by 
blank experiment. Then add 10 cc of ammonium hydroxid (specific 
gravity 0.90), and allow the whole to stand for at least three hours; 
separate the precipitate by filtration and wash it free, or nearly so, of 



METHODS OF ANALYSIS FOR CERTIFIED COLORS. 



213 




BOfi£- TO CO/V7^/Af 



COTTON MO/S7TNEO 



dye with ammoniuin hydroxid containing one-tenth its volume of 
ammonia (specific gravity 0.90). Dissolve the precipitate from the 
paper with 1 : 1 nitric acid, the washings being collected in a large 
porcelain crucible; add 5 cc of sulphuric acid to the contents of the 
crucible, and evaporate the whole almost to dryness. It is not nec- 
essary that the solution should be colorless at this point, a brown 
colored solution giving equally accurate results. Add 20 cc of water 
to the residue in the crucible and then 10 cc of 
a saturated solution of sulphur dioxid; evapo- 
rate the solution to a sirupy consistency to 
remove the sulphur dioxid, and then take up 
in 20 cc of water and place in a 30-cc evolution 
bottle, add 5 cc of concentrated sulphuric acid, 
and determine the arsenic in the form of appa- 
ratus iS^%. 1) used by Bishop in his modification 
of the Gutzeit test, the stains obtained being 
compared with those given by known amounts 
of arsenic. 

The apparatus used by Bishop consists of 
the following parts; A 30-cc salt mouth evo- 
lution bottle into which is fitted a one-hole 
rubber stopper carrying a glass tube 6.5 cm 
long with an internal diameter of 1 cm, this 
tube in turn being provided with a one-hole 
rubber stopper fitted with another tube of the 
same diameter and 5.5 cm long, the diameters 
of both tubes being constricted at the points at 
wliich they are inserted in the rubber stoppers. 
A third glass tube 15 cm long, having an in- 
ternal diameter of 2.5 mm, is fitted into the 
second at its upper end by means of a rubber 
stopper. The first tube contains a strip of filter 
paper which has been saturated with a 5 per 
cent solution of lead acetate and dried. The 
second tube contains a loosely packed plug of 
cotton-wool freshly moistened with a 1 per cent fig. i.-Apparatus for the 

solution of lead acetate. Into the topmost tube determination of arsenic. 

is inserted the strip of sensitized paper to receive the arsenic s tain. The 
arsin is generated by introducing into the evolution bottle six pieces of 
Kahlbaum's stick zmc (arsenic-free for forensic purposes) weighing 
in all about 8 grams, and to assist in an active and constant evolution 
of gas a disk of platinum is also placed m each bottle to form an elec- 
trolytic couple. The evolution of gas is allowed to proceed for one 
hour. The stains are produced on strips of hard pressed white paper 
(2 mm wide and 120 mm long) that has been sensitized by being 



eB. /3C£77frE^ fiopefr 



-/OZ.eor7Z£ 



214 CQAL-TAE COLOKS USED IN FOOD PKODUCTS. 

dipped in a 5 per cent alcoholic solution of mercuric chlorid and then 
dried. (Note. — It has recently been found that mercuric bromid yields 
stains that are more evenly distributed and also produces standards 
that are incomparably more permanent.) For purposes of com- 
parison it is better not to develop the strips stained by the arsin, 
though some prefer to dip the stains in ammonium hydroxid, which 
causes them to become black. A blank is run with each set of 
determinations. 

ETHER EXTRACTIVES. 

Dissolve 10 grams of color in 150 cc of water and extract in a separa- 
tory funnel with ether that has been washed with water (using three 
150 cc portions of water for each liter of ether). Extract the color 
solution with two 100 cc portions of this ether, shaking thoroughly 
for one minute, and wash the combined ether extract successively 
with 35, 20, and 10 cc of water made alkaline or acid, as the case 
requires, with 1 cc of tenth normal alkali or acid per 100 cc of water. 
Decant the ether from the mouth of the separatory and rinse the funnel 
once with 5 cc ether. The color solution is first extracted neutral, 
the extracted solution being then rendered alkaline with 2 cc of a 10 
per cent solution of caustic soda and again extracted with two 100-cc 
portions of ether. In acidifying for the third extraction, add twice 
the amount of hydrochloric acid (1 to 3) necessary to neutralize the 
alkali, and repeat the extraction with two 100-cc portions of ether. 
Place the neutral, alkaline, and acid extracts in a dust-free atmosphere, 
and allow the ether to evaporate spontaneously, after which dry the 
residues to constant weigh over sulphuric acid, using flat-bottomed 
dishes 2} inches in diameter, 1 J inches in height, and of about 100 cc 
capacity. The dishes should be thoroughly cleaned, wiped dry, and 
allowed to stand in a sulphuric acid desiccator at least two hours 
before weighing. In order to avoid the generation of static charges 
of electricity, they should not be wiped immediately before weighing. 
Run two blank determinations with each series of ether extracts, and 
deduct the average gain in weight of these two blanks from the weights 
obtained in the other determinations. 

SULPHATED ASH. 

Weigh accurately 0.5 to 1 gram of the color into a wide platinum 
dish, moisten with concentrated sulphuric acid, and ignite cautiously, 
avoiding spattering; moisten the residue repeatedly with sulphuric 
acid and ignite until all the carbon is removed and a white or reddish 
ash is obtained. This is finally ignited at a fairly bright red heat, 
cooled, and weighed. The a(iueous solution of this ash should 
be neutral to litmus, and may be used in a quantitative test for 
potassium. 



METHODS OF ANALYSIS FOB CERTIFIED COLORS. 215 

CALCIUM. 

Digest the residue from the sulphated ash determination with 
hydrochloric acid, render the solution alkaline with ammonium 
hydroxid, filter, and precipitate the calcium in the filtrate with ammo- 
nium oxalate. The precipitate of calcium oxalate is filtered on a 
tared gooch, washed, dried at 100° C. and weighed as calcium oxalate, 
the calcium being calculated from the formula CaC204.H20. This 
method is applicable only in cases where the amount of calcium is 
very small. When the amount exceeds 0.5 per cent it should be 
determined by digesting the sulphated ash with ammonium sulphate 
solution made acid with hydrochloric acid, and precipitating the iron 
by an excess of ammonium hydroxid. The precipitate is washed, 
dissolved in hydrochloric acid, and reprecipitated, the filtrate and 
washings being added to those obtained from the first precipitate. 
The calcium is precipitated in the combined filtrates with ammonium 
oxalate, the oxalate being filtered, washed, ignited, and weighed in 
the usual way; the residue is weighed as oxid after ignition to bright 
redness. 

SULPHUR. 

Determine upon 0.2 to 0.3 gram portions by the Carius method 
(Gattermann, Practical Methods of Organic Chemistry, 1901, p. 81), 
using 3 cc of fuming nitric acid (sp. gr. 1.5), and heating the sealed 
tubes to 300° C. for at least eight hours. 

NITROGEN. 

Use the method of Dumas (Gattermann, Practical Methods of 
Organic Chemistry, 1901, p. 85). 

PONCEAU 3R. 

MOISTURE. 

Dry 1 to 2 grams of the finely ground dye at 109° to 110° C. in a 
current of dry hydrogen to constant weight. 

TOTAL INSOLUBLE MATTER. 

Determine as under Naphthol Yellow S, page 211. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 

Determine as under Naphthol Yellow S, page 211. 

SODIUM CHLORID (SEEKER AND MATHEWSON^S METHOD). 

Mix 2 grams of dye thoroughly with from 2 to 3 grams of sodium 
carbonate, moisten with water to form a paste, again mix, dry, and 
ignite at a low red heat. By moistening, drying, and reigniting a 



216 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

more complete destruction of organic matter is obtained. Break up 
the charred mass, introduce into a 200-cc graduated flask with about 
100 to 150 cc of hot water, and add an excess of potassium perman- 
ganate to oxidize sulphids. Destroy the excess of permanganate by 
adding sulphur dioxid solution until the red color changes to brown, 
then cool the mixture and make up to the mark with water. Filter 
through a dry paper, acidify 100 cc of the filtrate with nitric acid, 
and precipitate the chlorin as silver chlorid by the addition of silver 
nitrate. If the solution should be brownish from a trace of organic 
matter the silver chlorid does not readily coagulate and tends to pass 
through the filter. In this case a few drops of potassium permanganate 
solution are added to this acid mixture, the organic matter being 
almost instantly oxidized. The mixture is then decolorized with a 
few drops of sulphur dioxid solution, the silver chlorid is separated on 
a tared gooch, washed, ignited, and weighed in the usual manner. 
The following method may also be used for Ponceau BR: 
Dissolve 5 grams of the dye in 15C cc hot water, wash into a 250-cc 
graduated flask, and add 25 cc o£ a 10 per cent solution of barium 
nitrate. Cool the mixture, make up to the mark, and filter through a 
dry paper; acidify 100 cc of the filtrate, representing 2 grams of color, 
with nitric acid, and treat with silver nitrate solution, the precipi- 
tated silver chlorid being separated, washed, ignited, and weighed in a 
tared gooch crucible in the usual way. 

SODIUM SULPHATE. 

Dissolve 2 grams of dye in 100 cc of hot water, wash into a 200-cc 
graduated flask, add 50 grams of pure sodium chlorid, cool, and make 
up to the mark with water. Filter through a dry filter, dilute 100 cc 
of the filtrate to 300 cc, acidify with hydrochloric acid and precipi- 
tate the sulphates with barium chlorid. Filter, wash, ignite, and 
weigh in a tared platinum gooch in the usual way. 

HEAVY METALS. 

Determine as given under Naphthol Yellow S, page 212. 

ARSENIC. 

Determine as given under Naphthol Yellow S, page 212. 

ETHER EXTRACTIVES. 

Determine as given under Naphthol Yellow S, page 214. 

SULPHATED ASH. 

Determine as given under Naphthol Yellow S, page 214. 



METHODS OF ANALYSIS FOR CERTIFIED COLORS. 217 

CALCIUM. 

Determine as given under Naphthol Yellow S, page 215. 

SULPHUR. 

Determine as given under Naphthol Yellow S, page 215. 

NITROGEN (seeker AND MATHEWSON's METHOD). 

Treat 2 grams of the color with 25 cc of a saturated solution of 
sulphur dioxid and 1 gram of zinc dust and warm the mixture gently 
until it becomes colorless. This should take place in from two to three 
minutes, but if it does not add more sulphur dioxid solution in small 
portions at a time until the color is destroyed. Then add 30 cc of con- 
centrated sulphuric acid and 0.7 gram of mercuric oxid or its equiva- 
lent of metallic mercury and digest the mixture, make alkaline, and 
distil as directed on page 6, Bulletin 107, Revised, Bureau of Chemistry, 
United States Department of Agriculture, under the Kjeldahl process. 

CRUDE CUMIDIN. 

Dissolve 20 grams of dye in 400 cc of hot water and pour the solu- 
tion, a little at a time, into a reducing solution composed of 75 grams 
of stannous chlorid dissolved in 180 cc of concentrated hydrochloric 
acid. Heat the mixture on a steam bath until it is straw colored, 
cool, add an excess of sodium hydroxid, and extract in a separatory 
funnel with ether. Separate the ether layer and distil off the solvent 
until the residue measures about 50 cc. Then cautiously heat over 
the steam with constant agitation until the odor of ether disappears, 
after which the last of the moisture is removed by introducing a few 
pieces of solid caustic soda and allowing to stand. The residue con- 
sists of crude cumidin and should boil above 220° C. Cumidin 
nitrate is sparingly soluble in water. 

ORANGE I. 
MOISTURE. 

Determine as given under Ponceau 3E-, page 215. 

TOTAL INSOLUBLE MATTER 

Determine as given under Naphthol Yellow S, page 211. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211. 

SODIUM CHLORID. 

Determine as given under Ponceau 311, page 215. 



218 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

SODIUM SULPHATE. 

Dissolve 1 gram of dye in 100 cc water contained m a 200-cc grad- 
uated flask and treat the solution with 60 cc of a 20 per cent solution 
of potassium chlorid. Make the mixture up to the mark with 
water, shake, filter through a dry paper, dilute an aliquot of 100 cc 
of the filtrate to 200 cc, acidify with 1 cc of 10 per cent hydro- 
chloric acid, treat with 5 cc of 10 per cent barium chlorid solution, 
and allow to stand over night. If a precipitate has been formed 
this is separated, ignited, and weighed in the usual way. 

HEAVY METALS. 

Determine as given under Naphthol Yellow S, page 212. 

ARSENIC (seeker AND SMITH' S METHOD). 

Dissolve 2 grams of dye in a mixture of 130 cc water and 70 cc of 
95 per cent alcohol. Add about 10 cc of strong bromin water to 
convert any arsenite to arsenate. Make the mixture alkaline with a 
few cubic centimeters of strong ammonium hydroxid and add, from 
a pipette, 20 cc of a sodium phosphate solution containing 100 
grams of crystallized sodium phosphate per liter, after which mag- 
nesia mixture (containing 55 grams of hydrated magnesium chlorid, 
55 grams of ammonium chlorid, and 88 cc of ammonium hydroxid, 
sp. gr. 0.9, per liter) is added from a burette, stirring vigorously. 
The amount of magnesia mixture to be added should be in slight 
excess of that necessary to precipitate the phosphate completely, 
and should be previously ascertained by a blank experiment. Finally 
add 10 cc of ammonium hydroxid (sp. gr. 0.96) and allow the whole 
to stand for at least eight hours. Separate the precipitate by filtra- 
tion and wash it free, or nearly so, of dye with a mixture of one-third 
alcohol and two-thirds water containing one-tenth its volume of 
ammonium hydroxid (sp. gr. 0.90) . Dissolve the precipitate from the 
paper with 20 per cent sulphuric acid, the washings being collected 
in a large porcelain crucible. Add 5 cc of concentrated nitric acid 
to the contents of the crucible and evaporate the whole almost to 
dryness. The mixture need not be colorless at this point, a brown 
colored solution giving equally accurate results. Add 20 cc of water 
to the residue in the crucible and then 10 cc of a saturated solution 
of sulphur dioxid. Evaporate the solution to a syrupy consistency 
to remove sulphur dioxid, and then take up in 20 cc of water, place 
in a 30-cc evolution bottle, add 5 cc of concentrated sulphuric acid, 
and determine the arsenic by the modified Gutzeit method as given 
under Naphthol Yellow S, page 213. 

ETHER EXTRACTIVES. 

Determine as given under Naphthol Yellow S, page 214 



METHODS OF ANALYSIS FOR CERTIFIED COLORS. 219 

SULPHATED ASH. 

Determine as given under Naphthol Yellow S, page 214. 

CALCIUM. 

Determine as given under Naphthol Yellow S, page 215. 

SULPHUR. 

Determine as given under Naphthol Yellow S, page 215. 

NITROGEN. 

Determine as given under Ponceau 3E,, page 217. 

TEST FOR ORANGE II (SMITH AND MATHEWSON's METHOD). 

The following solutions are required : 

(1) Fifteen per cent titanium trichlorid. 

(2) Freshly prepared diazotized sulphanilic acid. Heat a mixture 
composed of 1 gram of sulphanilic acid, 10 cc of water, and 20 cc of 
concentrated hydrochloric acid on a steam bath for five minutes with 
occasional shaking. Cool to about 10° C. and add slowly 10 cc of a 1 
per cent solution of sodium nitrite. Allow the mixture to stand at 
about 10° for 10 minutes, dilute to 1 liter, and shake until all the 
solid particles have dissolved. 

(3) Stannous chlorid, prepared by dissolving 40 grams of stannous 
chlorid in 100 cc of concentrated hydrochloric acid. Dilute this ten 
times with water, immediately before using. 

Place 2 cc of a 0.1 per cent solution of the dye in a colorimeter tube 
having a capacity of about 100 cc, add a small drop of titanium trichlo- 
rid solution and shake until the mixture is decolorized. Standards 
containing the same quantity of color composed of a mixture of pure 
Orange I and known amounts of Orange II are treated in the same 
way, the volume of the solution at this point to measure less than 5 cc. 
Dilute the decolorized solutions to 50 cc with 95 per cent alcohol and 
equalize the temperature by immersing the tubes in water at room 
temperature. (Note. — A slight coloration that may develop at this 
point may be disregarded.) Allow the tubes to stand in the water 
for about five minutes, add 2 cc of the diazotized sulphanilic acid, 
and mix thoroughly. If the titanium trichlorid has not been used 
in too great excess, the first few drops of the diazotized sulphanilic 
acid will cause a formation of color. Allow the coupling to proceed 
for three minutes and then add 5 cc of the diluted stannous chlorid 
with vigorous shaking. In two minutes the blue color due to Orange I 
will disappear, leaving only the pink caused by the couphng product 
of Orange II. The depth of color in the tube containing the dye 
under examination may then be compared to the standards. 



220 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

AMARANTH. 
MOISTURE. 

Determine as given under Ponceau 3R, page 215. 

TOTAL INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S^ page 211. 

SODIUM CHLORID. 

Determine as given under Ponceau 3R, page 215. 

SODIUM SULPHATE. 

Dissolve 2 grams of dye in 100 cc of warm water in a 200-cc grad- 
uated flask, and add 36 grams of pure sodium chlorid. Allow the 
mixture to stand with frequent shaking for one hour, and after cooling 
make up to the mark with a saturated salt solution. Shake the 
mixture and filter through a dry paper; dilute 100 cc of the filtrate 
(representing 1 gram) with water, acidify with hydrochloric acid, and 
precipitate the sulphates with barium chlorid. The precipitate is 
separated, washed, and ignited upon a tared platinum gooch crucible. 

HEAVY METALS. 

Determine as given under Naphthol Yellow S, page 212. 

ARSENIC. 

Determine as given under Naphthol Yellow S, page 212. 

ETHER EXTRACTIVES. 

Determine as given under Naphthol Yellow S, page 214. 

SULPHATED ASH. 

Determine as given under Naphthol Yellow S, page 214. 

CALCIUM. 

Determine as given under Naphthol Yellow S, page 215. 

SULPHUR. 

Determine as given under Naphthol Yellow S, page 215. 



METHODS OF ANALYSIS FOR CERTIFIED COLORS. 221 

NITROGEN. 

Determiiie as given under Ponceau 3E,, page 217. 

LIGHT GREEN S F YELLOWISH. 
MOISTURE. 

Determine as given under Ponceau 3R, page 215. 

TOTAL INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211. 

SODIUM CHLORID. 

Determine as given under Ponceau 3R, page 215. 

SODIUM SULPHATE. 

Dissolve 5 grams of the color in 100 cc of water, warming by means 
of a gentle heat. Dissolve 11 grams of safrania in a separate portion 
of 400 cc of water, also by warming, taking care in both instances to 
prevent loss by evaporation. Mix the two solutions, shake thor- 
oughly, and filter through a dry filter. Kender an ahquot portion 
of the filtrate alkaline with sodium hydroxid and remove the excess 
of safranin by shaking with two successive portions of amyl alcohol. 
Wash the combined amyl alcohol layers with two portions of water 
and add the washings to the main aqueous solution, which is then 
acidified with hydrochloric acid and sulphates determined in the usual 
maimer by preciptiation with barium chlorid as barium sulphate. 

HEAVY METALS. 

Determine as given under Naphthol Yellow S, page 212. 

ARSENIC. 

Determine as given under Naphthol Yellow S, page 212, 

ETHER EXTRACTIVES. 

Determine as given under Naphthol Yellow S, page 214, 

SULPHATED ASH. 

Determine as given under Naphthol Yellow S, page 214. 

CALCIUM. 

Determine as given under Naphthol Yellow S, page 215 



222 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

SULPHUR. 

Determine as given under Naphthol Yellow S, page 215. 

NITROGEN. 

Determine on 2-gram portions by Gunning's modification of the 
Kjeldahl process, using a little copper sulphate to assist the oxidation 
(see page 7, Bulletin 107, Revised, Bureau of Chemistry, United 
States Department of Agriculture) . 

EBYTHROSIN. 

MOISTURE. 

Determine as given under Ponceau 3E,, page 215. 

TOTAL INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER 

Determine as given under Naphthol Yellow S, page 211. 

SODIUM CHLORID. 

Dissolve 5 grams of the dye in 400 cc water and acidify with dilute 
nitric acid. Make the mixture up to 500 cc with water, and then 
filter through a dry filter. Determine chlorids in an aliquot of 200 cc 
of the filtrate by precipitation with silver nitrate, washing, igniting, 
and weighing the silver chlorid in a tared gooch crucible in the usual 
maimer. 

SODIUM SULPHATE. 

Employ another aliquot of the filtrate obtained after precipitating 
the color acid as above in. the determination of sulphates, precipi- 
tating the latter as barium sulphate in the usual maimer. 

HEAVY METALS. 

Determine as given under Naphthol Yellow S, page 212. 

ARSENIC (seeker AND SMITH's METHOD). 

Dissolve 16 grams of dye in 370 cc of water, add 5 cc of strong 
bromin water, and finally 25 cc of dilute sulphuric acid (1 to 4). 
Shake thoroughly and filter through a dry filter. Place an aliquot 
of 250 cc, representing 10 grams of color from the filtrate, in a porce- 
lain casserole, add 5 cc concentrated nitric acid (very important to 
prevent loss of arsenic) , and evaporate till fuming has ceased. Reduce 
the residue with sulphur dioxid solution, evaporate to small bulk, 
and determine the arsenic in the form of apparatus used by Bishop in 



METHODS OF ANALYSIS FOR CERTIFIED COLORS. 223 

his modification of the Gutzeit test. See under Naphthol Yellow S, 
pages 212 and 213. (Note. — It is somewhat difficult at times to 
recover 250 cc of filtrate, but less may be used and a correction made, 
if necessary.) 

ETHER EXTRACTIVES. 

Determine as given under Naphthol Yellow S, page 214, omitting 
the acid extraction. 

SULPHATED ASH. 

Determine as given under Naphthol Yellow S, page 214. 

lODIN, BROMIN, AND CHLORIN (CORNELISON^S METHOD). 

Mix 0.2 to 0.3 gram of the sample with 2 grams of pure potassium 
bichromate and 15 cc of strong sulphuric acid in the evolution flask 
of an apparatus made entirely of glass, with ground-glass joints. 
Thoroughly mix the contents of the evolution flask, so that all lumps 
are disintegrated, and then heat at 100° C. for 15 minutes, after 
which raise the temperature to 150° C. for thirty minutes, a cur- 
rent of air dried over calcium chlorid and potassium hydroxid being 
drawn through the apparatus during this time. lodin remains in 
the evolution flask as iodic acid; bromin passes off as such, and may 
be absorbed by allowing the air passing through the apparatus to 
bubble through 1 per cent sodium hydroxid. Chlorin passes out of 
the evolution flask as chromyl chlorid, and may also be absorbed in 
sodium hydroxid. Cool the mixture containing the iodic acid, and 
reduce the chromic acid by addition of sulphur dioxid, about 20 cc 
of a saturated solution being required. When enough has been 
added, the precipitated iodin redissolves, and the clear green color 
of chrome alum appears. Filter, wash the paper with distilled water, 
dilute the filtrate and washings to about 300 cc, and add an excess of 
silver nitrate. Boil till the silver iodid has flocculated, allow to stand 
for a few hours, and separate and weigh the silver iodid in a tared 
gooch. 

It sometimes happens that the mixture containing the iodic acid, 
after the reduction with sulphur dioxid, becomes turbid, owing, 
apparently, to separation of a basic chromium sulphate. Very often 
the turbidity can not be removed by filtering, and it has been found 
advisable in this case to reject the determination and begin anew. 

IODIN (seeker and mathewson's method).^ 

Place from 0.3 to 0.4 gram of the erythrosin in a porcelain casserol, 
dissolve this in 5 cc of a 10 per cent sodium hydroxid solution, then 
add 35 cc of a 7 per cent solution of potassium permanganate. After 

1 U. S. Dept. Agr., Bureau of Chemistry, Circular 65. The estimation of iodin in organic compounds 
and its separation from other halogens. 



224 COAL-TAK. CJOL.ORS USED IN FOOD PRODUCTS. 

mixing, cover the vessel with a watch crystal, and add 10 cc of 
nitric acid, keeping the dish covered. Agitate the mixture, place 
on a steam bath, and keep covered until spattering ceases, after 
which remove the watch glass and allow evaporation to proceed to 
dryness.^ Treat the residue with 5 cc of 7 per cent potassium per- 
manganate and 5 cc of concentrated nitric acid and again evaporate 
to dryness. Then add about 50 cc of water and 5 cc of concentrated 
nitric acid to the residue, following this by 40 cc of a saturated solu- 
tion of sulphur dioxid, and allow the whole to stand with occasional 
stirring (breaking up the lumps with a glass rod) until the hydrated 
oxid of manganese has dissolved. Filter, and wash the paper with 
water. Add an excess of silver nitrate to the filtrate, and boil until 
sulphur dioxid has been expelled and the silver iodid has flocculated. 
Separate, wash, and weigh the precipitate in the usual manner. 

TOTAL HALOGENS. 

Mix 0.5 to 1 gram of the dye with 4 grams of potassium carbonate, 
moisten to a paste, again thoroughly mix, cover with a layer of dry 
potassium carbonate, dry, and ignite at a low red heat. Break up 
the char thoroughly, digest with about 200 cc water, and filter. 
Wash the insoluble matter until the washings no longer react with 
silver nitrate; then acidify the filter and washings with nitric acid 
and precipitate the halogens in the usual way as silver salts. 

INDIGO DISULPHOACID. 
MOISTURE. 

Determine as given under Ponceau 3E,, page 215. 

TOTAL INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211. 

NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 

Determine as given under Naphthol Yellow S, page 211, 

SODIUM CHLORID. 

Determine as given under Ponceau 3R, page 215. 

SODIUM SULPHATE. 

Dissolve 2 grams of the dye in about 1 60 cc of water and treat the 
solution with 40 giams of pure sodium chioiid. After the salt has 
dissolved, make up the volume to exactly 200 cc. Shake the mix- 

1 In the operation of drying particular care should be obst. . ed to prevent access of reducing gases to the 
mixture. 



ADDENDA. 226 

ture thol'oughly and filter through a dry filter. Dilute 50 cc of the 
filtrate with 200 cc of water, acidify with 1 cc of 10 per cent hydro- 
chloric acid, and treat with an excess of barium chlorid solution. 
After standing overnight, the precipitate is separated, washed, 
ignited, and weighed in the usual way. 

HEAVY METALS. 

Determine as given under Naphthol Yellow S, page 212. 

ARSENIC (seeker AND SMITH's METHOD). 

Treat 10 grams of dye in a Kjeldahl flask with 100 cc water and 
10 cc concentrated nitric acid. Warm gently and finally boil until 
all action has ceased. Transfer to a beaker, make alkaline with 
ammonium hydroxid, and proceed from this point, as in the case of 
the solution of Naphthol Yellow S, page 212, continuing from the 
point at which sodium phosphate is added. 

ETHER EXTRACTIVES. 

Dissolve 3 grams of dye in 200 cc of water and extract with ether, 
as directed under Naphthol Yellow S, page 214. 

SULPHATED ASH. 

Determine as given under Naphthol Yellow S, page 214. 

CALCIUM. 

Determine as given under Naphthol Yellow S, page 215. 

SULPHUR. 

Determine as given under Naphthol Yellow S, page 215. 

NITROGEN. 

Determine as given under Light Green SF Yellowish, page 222. 

XVIII. ADDENDA. 

ADDITIONAL EXAMINATION OF COAL-TAR DYES. 

Since the foregoing report was written the chemical examination of 
the coal-tar dye specimens collected in the summer of 1907 has been 
completed. This investigation shows that 7 of the Green Table num- 
bers then reported were not on the market, although those furnishing 
the specimens included them at the time that the samples were sup- 
plied. These numbers are as follows: Tiot physiologically examined, 

97291°— Bull. 147—12 15 



226 COAL-TAR COLORS USED IN FOOD PRODUCTS. 

G. T. 49, 60, 104, 518, 523; physiologically examined, with unfavora- 
ble result, G. T. 516; with favorable result, G. T. 520. 

The chemical examination also shows that each of 9 additional 
Green Table numbers occurred once among the unreported numbers. 
They are as follows: not examined physiologically, G. T. 20, 328; 
examined physiologically: with unfavorable results, G. T. 602; with 
favorable results, G. T. 92, 477, 521 ; \vith contradictory results, G. T. 
16, 43, 163. G. T. 20 is anilin azo (1:8) dioxy naphthalene (3:6) 
disulpho acid. G. T. 328 is diamino-stilbene-disulpho acid-disazo- 
phenol. 

This chemical examination finally shows that beside the Green 
Table numbers there occurred, once each, the following: sulphonated 
Victoria Blue B and a sulphonated rhodulin and twice, amido-azo- 
toluene-azo-alpha-naphthol . 

It is clear that this revised statement of facts is without influence 
on the 7 permitted dyes selected; its only effect is to add G. T. 92 
(yellow), 477 (blue), and 521 (red) (each occurring but once) to, and 
to subtract 520 (red) (said to occur t^vice) from, the 16 dyes (page 166) 
from among which the 7 permitted dyes were selected, thus giving 18 
instead of 16 dyes to choose from; however, the final selection is 
wholly unaffected thereby. It is also clear that any and all inter- 
mediate conclusions or comparisons are only slightly and immaterially 
affected, if at all, by the results of this additional examination. 



SUPPLEMENTARY LIST OF TRADE NAMES OF COAL-TAR COLORS.^ 



Acid Yellow S (4). 

Alkali Blue (477). 

Azo Acid Rubin 2B (107). 

Azo Yellow (92). 

Crocein Scarlet extra (164). 

Dimethylanilin Orange (87). 

Eosin, water soluble (512). 

Fast Red A (102). 

Fast Red B (65). 

Fast Red E (105). 

Fast Yellow Y (8). 

Indian Yellow (92). 



IndulinRandB (601). 
Leucindophenol (572) . 
Methyl Orange (87). 
Naphthylamin Pink (614) . 
Naphthylene Blue R in crystals (639). 
Soluble Blue 8B and lOB (479). 
Sulphur Yellow (4). 
Thiochromogen (659) . 
Victoria Blue (488). 
Wool Black (166). 
Yellow T (84). 



XIX. INDEX OF AUTHORITIES QUOTED. 



[References are made to important citations exclusive of pages 76 to 152, except in cases where the author 

is not cited elsewhere.] 



Page. 

Arloing and Cazeneuve 90 

Beckh 55 

Behal 177 

Bergeron and Clouet 119 

Beythien and Hempel 173 

Bishop 213 

Bokorny 54 

Braunschweig and Graefe 121 

Buss 71 

Cazeneuve 93 

Cazeneuve and Arloing. 90 

Cazeneuve and Lepine 42 

Chlopin 59,72,75,181 

Clouet and Bergeron 119 

Combemale and Francois 142 

Confectioners' List 74 

Dietrich , 37 

Erdmann 44, 57 

Ernst 170 

Fraenkel, J 25 

Fraenkel, S 60, 74, 160, 16&, 180 

Francois and Combemale 142 

Frentzel 26 

Galliard 143 

Gattermann 215 

Georgievics 58 

Graefe and Braunschweig 121 



Green, Arthur G 

Gudeman 

Heidenhain 

Hempel & Beythien.. 

Henley 

Houghton 

Hueppe 

International "^Tiite 



Cross Con- 



gress 

Kayser 

Robert 

Koenig 

Kohnstamm, E . G 

Lehmann 

Lepine & Cazeneuve 

Lewin 

Lieber 

Ludwig 

Meyer 

Muttelet 

National Confectioners' Associa 

tion 

Neufeld, C. A 

Patents, H. R. Committee on 

Penzoldt 

Pfeffer 

Possetto 



Page. 
15 
24 
52 
173 
25 
55 
34 

172 

44 

83 

60 

190 

57, 157 

42 

58 

74 

24, 191 

24,60 

171 

30,45 
14 
61 
55 
51, 180 
26 



1 See also page 148. 



227 






COAL-TAK COLORS USED IX FOOD PRODUCTS. 



'U. 



Page. 

Rosenstiehl 54 

Santori 47, 158 

Schacherl 45, 75, 191 

Schultz 56 

Society of Swiss Analytical Chem- 
ists 43, 75 

Stilling 55, 56, 57, 180 

Canton of Tessin 75 

Tschirch 43, 57 



Page. 

V. Raumer \.. 37 

Weyl 23, 24, 26, 44, 58, 181 

Weyl (Leffman translation) 14, 

37, 74, 179, 181 

Williams, H. W 55 

Winogradow 52 

Winton 24, 59 

Young 159 



'\ 



O 



IBJL'12 



